| Ingredients | Amount Per Serving |
|---|---|
|
(Ascorbic Acid)
|
250 mg |
|
(Niacinamide)
(Niacin (Form: as Niacinamide) )
|
30 mg |
|
(as Pyridoxal 5-Phosphate)
(Vitamin B6 (Form: as Pyridoxal-5-Phosphate) )
|
500 mcg |
| 250 mcg | |
|
(Methylcobalamin)
(Vitamin B12 (Form: as Methylcobalamin) )
|
35 mcg |
|
(Ca)
|
16 mg |
|
(B-Alanine)
|
1.6 Gram(s) |
| 1 Gram(s) | |
|
C4 Ripped Blend
|
1 Gram(s) |
|
(bean)
(standardized for Chlorogenic Acids)
(Green Coffee bean extract (Form: standardized for Chlorogenic Acids) PlantPart: bean )
|
|
|
(Capsicum annuum )
(fruit)
|
|
|
(Coleus forskohlii )
(root)
|
|
|
Explosive Energy Blend
|
371 mg |
| 150 mg | |
|
(Mucuna pruriens )
(seed)
(standardized for L-Dopa)
(Velvet Bean (Mucuna pruriens) seed extract (Form: standardized for L-Dopa) PlantPart: seed Genus: Mucuna Species: pruriens )
|
Citric Acid, Natural & Artificial flavors, Malic Acid, Calcium Silicate, Silicon Dioxide (Alt. Name: SiO2), Sucralose, Acesulfame Potassium, FD&C Blue Lake #1
Below is general information about the effectiveness of the known ingredients contained in the product C4 Ripped Icy Blue Razz. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
Below is general information about the safety of the known ingredients contained in the product C4 Ripped Icy Blue Razz. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
POSSIBLY SAFE ...when used orally and appropriately for up to 3 years (5311,18113,30784,30785,30778). When used topically for up to 8 weeks (111125). ...when used intravenously and appropriately (5308,5309,5310,5311,5312,5313).
PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.
POSSIBLY SAFE ...when used orally and appropriately, short-term. Oral beta-alanine, including a specific commercial product (CarnoSyn, Natural Alternatives International), has been used with apparent safety in doses up to 6.4 grams daily for 12 weeks in younger adults (14611,16025,16439,16441,18227,94357,97972,101028,101029,104144,106717), and up to 3.2 grams daily for 12 weeks in adults aged 55 years and older (16442,97955,97961,97965).
PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using in medicinal amounts.
LIKELY SAFE ...when used orally, parenterally, or rectally and appropriately. Caffeine has Generally Recognized As Safe (GRAS) status in the US (4912,98806). Caffeine is also an FDA-approved product and a component of several over-the-counter and prescription products (4912,11832). According to a review by Health Canada, and a subsequent large meta-analysis conducted in the US, doses of caffeine up to 400 mg daily are not associated with significant adverse cardiovascular, bone, behavioral, or reproductive effects in healthy adults (11733,98806). The US Dietary Guidelines Advisory Committee states that there is strong and consistent evidence that consumption of caffeine 400 mg daily is not associated with increased risk of major chronic diseases, such as cardiovascular disease or cancer, in healthy adults (98806). This amount of caffeine is similar to the amount of caffeine found in approximately 4 cups of coffee. Keep in mind that only the amount of ADDED caffeine must be stated on product labels. The amount of caffeine from caffeine-containing natural ingredients such as coffee or green tea does not need to be provided. This can make it difficult to determine the total amount of caffeine in a given product.
POSSIBLY UNSAFE ...when used orally, long-term or in high doses (91063). Chronic use, especially in large amounts, can produce tolerance, habituation, psychological dependence, and other adverse effects (3719). Acute use of high doses, typically above 400 mg daily, has been associated with significant adverse effects such as tachyarrhythmia and sleep disturbances (11832). Keep in mind that only the amount of ADDED caffeine must be stated on product labels. The amount of caffeine from caffeine-containing natural ingredients such as coffee or green tea does not need to be provided. This can make it difficult to determine the total amount of caffeine in a given product.
LIKELY UNSAFE ...when used orally in very high doses. The fatal acute oral dose of caffeine is estimated to be 10-14 grams (150-200 mg/kg). Serious toxicity can occur at lower doses depending on variables in caffeine sensitivity such as smoking, age, or prior caffeine use (11832,95700,97454,104573). Caffeine products sold to consumers in highly concentrated or pure formulations are considered to a serious health concern because these products have a risk of being used in very high doses. Concentrated liquid caffeine can contain about 2 grams of caffeine in a half cup. Powdered pure caffeine can contain about 3.2 grams of caffeine in one teaspoon. Powdered pure caffeine can be fatal in adults when used in doses of 2 tablespoons or less. As of 2018, these products are considered by the FDA to be unlawful when sold to consumers in bulk quantities (95700).
CHILDREN: POSSIBLY SAFE
when used orally or intravenously and appropriately in neonates under the guidance of a healthcare professional (6371,38340,38344,91084,91087,97452).
...when used orally in amounts commonly found in foods and beverages in children and adolescents (4912,11833,36555). Daily intake of caffeine in doses of less than 2.5 mg/kg daily are not associated with significant adverse effects in children and adolescents (11733,98806). Keep in mind that only the amount of ADDED caffeine must be stated on product labels. The amount of caffeine from caffeine-containing natural ingredients such as coffee or green tea does not need to be provided. This can make it difficult to determine the total amount of caffeine in a given product.
PREGNANCY: POSSIBLY SAFE
when used orally in amounts commonly found in foods.
Intakes of caffeine should be monitored during pregnancy. Caffeine crosses the human placenta, but is not considered a teratogen (38048,38252,91032). Fetal blood and tissue levels are similar to maternal concentrations (4260). The use of caffeine during pregnancy is controversial; however, moderate consumption has not been associated with clinically important adverse fetal effects (2708,2709,2710,2711,9606,16014,16015,98806,108814). In some studies consuming amounts over 200 mg daily is associated with a significantly increased risk of miscarriage (16014,37960). This increased risk seems to occur in those with genotypes that confer a slow rate of caffeine metabolism (98806). According to a review by Health Canada, and a subsequent large meta-analysis conducted in the US, up to 300 mg daily can be consumed during pregnancy without an increased risk of spontaneous abortion, stillbirth, preterm birth, fetal growth retardation, or congenital malformations (11733,98806). However, observational research in a Norwegian cohort found that caffeine consumption is associated with a 16% increased odds of the baby being born small for gestational age when compared with no consumption (100369,103707). The same Norwegian cohort found that low to moderate caffeine consumption during pregnancy is not associated with changes in neurodevelopment in children up to 8 years of age (103699). Advise patients to keep caffeine consumption below 300 mg daily during pregnancy. This is similar to the amount of caffeine in about 3 cups of coffee or tea.
PREGNANCY: POSSIBLY UNSAFE
when used orally in amounts over 300 mg daily.
Caffeine crosses the placenta, producing fetal blood concentrations similar to maternal levels (4260,98806). Consumption of caffeine in amounts over 300 mg daily is associated with a significantly increased risk of miscarriage in some studies (16014,98806). Advise patients to keep caffeine consumption below 300 mg daily during pregnancy. This is similar to the amount of caffeine in about 3 cups of coffee or tea. Additionally, high doses of caffeine throughout pregnancy have resulted in symptoms of caffeine withdrawal in newborn infants (9891). High doses of caffeine have also been associated with spontaneous abortion, premature delivery, and low birth weight (2709,2711,91033,91048,95949). In a cohort of mother/infant pairs with a median maternal plasma caffeine level of 168.5 ng/mL (range 29.5-650.5 ng/mL) during pregnancy, birth weights and lengths were lower in the 4th quartile of caffeine intake compared with the 1st. By age 7, heights and weights were lower by 1.5 cm and 1.1 kg respectively. In another cohort of mother/infant pairs with higher maternal pregnancy plasma caffeine levels, median 625.5 ng/mL (range 86.2 to 1994.7 ng/mL), heights at age 8 were 2.2 cm lower, but there was no difference in weights (109846).
LACTATION: POSSIBLY SAFE
when used orally in amounts commonly found in foods.
Caffeine intake should be closely monitored while breast-feeding. During lactation, breast milk concentrations of caffeine are thought to be approximately 50% of serum concentrations and caffeine peaks in breastmilk approximately 1-2 hours after consumption (23590).
LACTATION: POSSIBLY UNSAFE
when used orally in large amounts.
Caffeine is excreted slowly in infants and may accumulate. Caffeine can cause sleep disturbances, irritability, and increased bowel activity in breast-fed infants exposed to caffeine (2708,6026).
LIKELY SAFE ...when used orally or intravenously and appropriately. Calcium is safe when used in appropriate doses (7555,12928,12946,95817). However, excessive doses should be avoided. The Institute of Medicine sets the daily tolerable upper intake level (UL) for calcium according to age as follows: Age 0-6 months, 1000 mg; 6-12 months, 1500 mg; 1-8 years, 2500 mg; 9-18 years, 3000 mg; 19-50 years, 2500 mg; 51+ years, 2000 mg (17506). Doses over these levels can increase the risk of side effects such as kidney stone, hypercalciuria, hypercalcemia, and milk-alkali syndrome. There has also been concern that calcium intake may be associated with an increased risk of cardiovascular disease (CVD) and coronary heart disease (CHD), including myocardial infarction (MI). Some clinical research suggests that calcium intake, often in amounts over the recommended daily intake level of 1000-1300 mg daily for adults, is associated with an increased risk of CVD, CHD, and MI (16118,17482,91350,107233). However, these studies, particularly meta-analyses, have been criticized for excluding trials in which calcium was administered with vitamin D (94137). Other clinical studies suggest that, when combined with vitamin D supplementation, calcium supplementation is not associated with an increased risk of CVD, CHD, or MI (93533,107231). Other analyses report conflicting results and have not shown that calcium intake affects the risk of CVD, CHD, or MI (92994,93533,97308,107231). Advise patients not to consume more than the recommended daily intake of 1000-1200 mg per day, to consider total calcium intake from both dietary and supplemental sources (17484), and to combine calcium supplementation with vitamin D supplementation (93533).
POSSIBLY UNSAFE ...when used orally in excessive doses. The National Academy of Medicine sets the daily tolerable upper intake level (UL) for calcium according to age as follows: 19-50 years, 2500 mg; 51 years and older, 2000 mg (17506). Doses over these levels can increase the risk of side effects such as kidney stones, hypercalciuria, hypercalcemia, and milk-alkali syndrome. There has also been concern that calcium intake may be associated with an increased risk of cardiovascular disease (CVD) and coronary heart disease (CHD), including myocardial infarction (MI). Some clinical research suggests that calcium intake, often in amounts over the recommended daily intake level of 1000-1300 mg daily for adults, is associated with an increased risk of CVD, CHD, and MI (16118,17482,91350,107233). However, these studies, particularly meta-analyses, have been criticized for excluding trials in which calcium was administered with vitamin D (94137). Other clinical studies suggest that, when combined with vitamin D supplementation, calcium supplementation is not associated with an increased risk of CVD, CHD, or MI (93533,107231). Other analyses report conflicting results and have not shown that calcium intake affects the risk of CVD, CHD, or MI (92994,93533,97308,107231). Advise patients to not consume more than the recommended daily intake of 1000-1200 mg per day, to consider total calcium intake from both dietary and supplemental sources (17484), and to combine calcium supplementation with vitamin D supplementation (93533).
CHILDREN: LIKELY SAFE
when used orally and appropriately.
Calcium is safe when used in appropriate doses (17506).
CHILDREN: POSSIBLY UNSAFE
when used orally in excessive doses.
The Institute of Medicine sets the daily tolerable upper intake level (UL) for calcium according to age as follows: 0-6 months, 1000 mg; 6-12 months, 1500 mg; 1-8 years, 2500 mg; 9-18 years, 3000 mg (17506). Doses over these levels can increase the risk of side effects such as kidney stones, hypercalciuria, hypercalcemia, and milk-alkali syndrome.
PREGNANCY AND LACTATION: LIKELY SAFE
when used orally and appropriately (945,1586,3263,3264,17506).
The World Health Organization (WHO) recommends prescribing oral calcium supplementation 1.5-2 grams daily during pregnancy to those with low dietary calcium intake to prevent pre-eclampsia (97347).
PREGNANCY AND LACTATION: POSSIBLY UNSAFE
when used orally in excessive doses.
The Institute of Medicine sets the same daily tolerable upper intake level (UL) for calcium according to age independent of pregnancy status: 9-18 years, 3000 mg; 19-50 years, 2500 mg (17506). Doses over these amounts might increase the risk of neonatal hypocalcemia-induced seizures possibly caused by transient neonatal hypoparathyroidism in the setting of excessive calcium supplementation during pregnancy, especially during the third trimester. Neonatal hypocalcemia is a risk factor for neonatal seizures (97345).
LIKELY SAFE ...when used orally in amounts typically found in food. Capsicum has Generally Recognized as Safe (GRAS) status in the US (4912). ...when used topically and appropriately (7038,10650,105345). The active capsicum constituent capsaicin is an FDA-approved ingredient used in certain over-the-counter, topical preparations (272).
POSSIBLY SAFE ...when used orally and appropriately, short-term in medicinal amounts. A specific sustained-release chili extract (Capsifen) has been used safely in doses of up to 200 mg daily, for up to 28 days (105196). ...when used intranasally and appropriately, short-term. Capsicum-containing nasal sprays, suspensions, and swabs seem to be safe when applied multiple times over 24 hours or when applied daily or every other day for up to 14 days. Although no serious side effects have been reported in clinical trials, intranasal application of capsicum-containing products can be very painful (14322,14324,14328,14329,14351,14352,14353,14356,14357) (14358,14359,14360,15016,105204). POSSIBLY UNSAFE when used orally, long-term or in high doses. There is concern that long-term use or use of excessive doses might be linked to hepatic or kidney damage, as well as hypertensive crisis (12404,40569,40606). There is insufficient reliable information available about the safety of capsicum when injected.
CHILDREN: POSSIBLY UNSAFE
when used topically in children under 2 years old (272).
There is insufficient reliable information available about the safety of capsicum when used orally in children.
PREGNANCY: LIKELY SAFE
when used topically and appropriately (272).
PREGNANCY: POSSIBLY SAFE
when used orally and appropriately, short-term.
Capsicum 5 mg daily has been used for up to 28 days during the latter half of the second trimester and the third trimester (96457).
LACTATION: LIKELY SAFE
when used topically and appropriately (272).
LACTATION: POSSIBLY UNSAFE
when used orally.
Dermatitis can sometimes occur in infants when foods heavily spiced with capsicum peppers are ingested during lactation (739). Also, observational research suggests that intake of raw capsicum peppers during pregnancy is associated with an increased risk of sensitization to inhalant allergens in children by the age of 2 years (41021).
POSSIBLY SAFE ...when used orally and appropriately, short-term. Coleus extract 500 mg daily has been used for up to 3 months without significant adverse effects (91885,100851). ...when used intravenously and appropriately, short-term. Intravenous forskolin, a constituent of coleus, seems to be safe when given at an appropriate rate of 0.5 mcg/kg/minute and increased at 15 minute intervals to 1.0, 2.0, and 3.0 mcg/kg/minute up to 1 hour (7278,7279). ...when used by inhalation and appropriately. Single-dose inhalation of forskolin powder 10 mg from a Spinhaler inhalator seems to be safe and well-tolerated (7281). ...when used ophthalmologically and appropriately. Coleus suspension eye drops (1%) have been safely used in clinical studies (7282,7283,7284,7402,7403,7405).
POSSIBLY UNSAFE ...when used orally in higher doses. Although coleus extracts have been used with apparent safety in doses up to 1.4 grams daily for 2 months (91884), taking coleus extract in doses exceeding 500 mg daily has been associated with an increased incidence of adverse effects, which are primarily gastrointestinal (100851).
PREGNANCY: POSSIBLY UNSAFE
when used orally.
Evidence from animal research suggests that high doses of coleus can inhibit embryo implantation and/or delay fetal development (25174); avoid using.
LACTATION:
Insufficient reliable information available; avoid using.
POSSIBLY SAFE ...when used orally and appropriately. Powdered formulations of cowhage seed that are standardized to provide levodopa 75-400 mg daily have been used with apparent safety for up to 20 weeks (7020,7203,97266).
POSSIBLY UNSAFE ...when the hair of the cowhage bean pod is used orally or topically. The bean pod hairs are strong irritants and can cause severe itching, burning, and inflammation (18).
PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.
LIKELY SAFE ...when used orally or parenterally and appropriately. Folic acid has been safely used in amounts below the tolerable upper intake level (UL). The UL for folic acid is based only on supplemental folic acid and is expressed in mcg folic acid. Dietary folate is not included in UL calculations, as dietary folate consumption has not been associated with adverse effects. The UL for folic acid in adults is 1000 mcg (6241). In cases of megaloblastic anemia resulting from folate deficiency or malabsorption disorders such as sprue, oral doses of 1-5 mg per day can also be used safely until hematologic recovery is documented, as long as vitamin B12 levels are routinely measured (6241,7725,8739).
POSSIBLY SAFE ...when L-5-methyltetrahydrofolate (L-5-MTHF), the reduced form of folate, is used orally and appropriately, short-term. L-5-MTHF has been used with apparent safety at a dose of 416 mcg daily for 16 weeks (104913,104914) and a dose of 113 mcg daily for 24 weeks (104920). A specific L-5-MTHF product (Metafolin, Eprova) has been used with apparent safety at a dose of 1.3 mg daily for 12 weeks (104912).
POSSIBLY UNSAFE ...when used orally in large doses, long-term. Clinical research shows that taking folic acid daily in doses of 800 mcg to 1200 mcg for 3-10 years significantly increases the risk of developing cancer and adverse cardiovascular effects compared to placebo (12150,13482,16822,17041). Doses above 1 mg per day should also be avoided if possible to prevent precipitation or exacerbation of neuropathy related to vitamin B12 deficiency (6241,6242,6245). However, there is contradictory evidence suggesting that higher doses may not be harmful. There is some evidence that doses of 5 mg per day orally for up to 4 months can be used safely if vitamin B12 levels are routinely measured (7725). Also, other clinical research suggests that folic acid supplementation at doses up to 5 mg, usually in combination with vitamin B12, does not increase the risk of cancer when taken for 2-7 years (91312). Very high doses of 15 mg per day can cause significant central nervous system (CNS) and gastrointestinal side effects (505).
CHILDREN: LIKELY SAFE
when used orally and appropriately.
Folic acid has been safely used in children in amounts below the tolerable upper intake level (UL). The ULs for folic acid are based only on supplemental folic acid and are expressed in mcg folic acid. Dietary folate is not included in UL calculations, as dietary folate consumption has not been associated with adverse effects. The UL for children is: 1-3 years of age, 300 mcg; 4-8 years of age, 400 mcg; 9-13 years of age, 600 mcg; 14-18 years of age, 800 mcg (6241).
CHILDREN: POSSIBLY SAFE
when L-5-methyltetrahydrofolate (L-5-MTHF), the reduced form of folate, is used orally and appropriately.
One clinical study in infants aged 27 days and younger shows that consuming a formula containing L-5-MTHF (Metafolin, Merck & Cie) 10.4 mcg/100 mL daily has been used with apparent safety for up to 12 weeks (104918).
PREGNANCY AND LACTATION: LIKELY SAFE
when used orally and appropriately.
Folic acid 300-400 mcg is commonly used during pregnancy for prevention of neural tube defects (8739). Miscarriage rates and negative impacts on fetal growth have not been shown to increase with peri-conception supplemental folic acid intakes of 4 mg per day (91320,91322). However, other research shows that taking more than 5 mg per day during pregnancy may reduce development of cognitive, emotional, and motor skills in infants (91318). Also, the tolerable upper intake level (UL) of folic acid for pregnant or lactating women is 800 mcg daily for those 14-18 years of age and 1000 mcg daily for those 19 years and older (6241).
PREGNANCY AND LACTATION: POSSIBLY SAFE
when L-5-methyltetrahydrofolate (L-5-MTHF), the reduced form of folate, is used orally and appropriately, short-term.
L-5-MTHF has been used with apparent safety at a dose of 416 mcg daily for 16 weeks during lactation. Compared to folic acid, this form seems to further increase the folate concentration of red blood cells, but not breast milk (104913,104914).
POSSIBLY SAFE ...when used orally and appropriately. Green coffee extracts taken in doses up to 1000 mg daily, providing up to 500 mg chlorogenic acid, have been used with apparent safety for up to 12 weeks in clinical research (17971,17972,103954). A specific green coffee extract (Svetol, Naturex) has been used with apparent safety in doses up to 200 mg five times daily for up to 12 weeks (17981,17982,17983). Green coffee also contains caffeine, although in lower amounts than regular coffee. One cup of green coffee contains about 20-50 mg of caffeine, compared with about 100 mg in one cup of regular coffee. According to a review by Health Canada, and a subsequent large meta-analysis conducted in the US, doses of caffeine up to 400 mg daily are not associated with significant adverse cardiovascular, bone, behavioral, or reproductive effects in healthy adults (11733,98806). The US Dietary Guidelines Advisory Committee states that there is strong and consistent evidence that consumption of caffeine 400 mg daily is not associated with increased risk of major chronic diseases, such as cardiovascular disease or cancer, in healthy adults (98806). Keep in mind that only the amount of ADDED caffeine must be stated on product labels. The amount of caffeine found in ingredients such as green coffee, which naturally contains caffeine, does not need to be provided. This can make it difficult to determine the total amount of caffeine in a given product.
PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.
LIKELY SAFE ...when used orally and appropriately. L-carnitine has been safely used in clinical trials lasting up to 12 months (1947,3620,3621,3623,3624,3625,3626,3627,3628,3629) (3630,3639,4949,8047,9790,12352,16104,16105,16106,16107) (16109,16110,23437,26496,26499,58150,58156,58161,58169,58182) (58189,58204,58207,58209,58213,58294,58523,58554,58556,58647) (58679,58715,58778,58793,58830,58831,58882,59023,59029,59043) (90624,90633,104177,111872,111876,111883,111884,111891,111898). ...when used parenterally as an FDA-approved prescription medicine. Avoid using D-carnitine and DL-carnitine. These forms of carnitine can act as competitive inhibitors of L-carnitine and may cause symptoms of L-carnitine deficiency (1946).
CHILDREN: POSSIBLY SAFE
when used orally or intravenously and appropriately.
L-carnitine has been safely used orally in children for up to 6 months (1433,3622,58166,58502,58981,59188,111887,111900,115351). It has also been safely used orally and intravenously in preterm infants (3633,3634,3635,3636,3637,58163,58190,58800,58902,59097)(59161).
PREGNANCY:
Insufficient reliable information available; avoid using.
LACTATION: POSSIBLY SAFE
when used orally.
Supplemental doses of L-carnitine have been given to infants in breast milk and formula with no reported adverse effects. The effects of large doses used while nursing are unknown, but L-carnitine is secreted in the breast milk (3616).
LIKELY SAFE ...when prescription products are used orally and appropriately (12033). ...when niacinamide supplements are taken orally in doses below the tolerable upper intake level (UL) set by the Institute of Medicine (IOM). The UL of niacinamide is 30 mg daily for adults 18 years of age and 35 mg daily for adults 19 years and older (6243).
POSSIBLY SAFE ...when used orally in doses greater than 30 mg but less than 900 mg daily. The European Food Safety Authority has set the tolerable upper intake level (UL) of niacinamide at 900 mg daily (104937). However, oral niacinamide has been safely used in doses up to 1500 mg daily for 12 weeks in some clinical trials (25561,94188,98940,107709,110502) and up to 1000 mg daily for 12 months in other trials (93362,113559,113560). ...when used topically and appropriately for up to 16 weeks (5940,93360,110497,110498,110501,113681,113683,113684).
CHILDREN: LIKELY SAFE
when used orally and appropriately.
Niacinamide has been safely used in children for up to 7 years in doses below the tolerable upper intake level (UL) (4874,9957). The UL of niacinamide for children by age is: 1-3 years, 10 mg daily; 4-8 years, 15 mg daily; 9-13 years, 20 mg daily; 14-18 years, 30 mg daily (6243).
PREGNANCY AND LACTATION: LIKELY SAFE
when used orally in amounts that do not exceed the tolerable upper intake level (UL) for niacinamide.
The UL of niacinamide during pregnancy and lactation is 30 mg daily for those 14-18 years of age and 35 mg daily for those 19 years and older (6243). There is insufficient reliable information available about the safety of larger oral doses of niacinamide or topical niacinamide; avoid using.
LIKELY SAFE ...when used orally in amounts commonly found in foods. Tyrosine has Generally Recognized as Safe (GRAS) status in the US (4912).
POSSIBLY SAFE ...when used orally and appropriately in medicinal amounts, short-term. Tyrosine has been used safely in doses up to 150 mg/kg daily for up to 3 months (7210,7211,7215). ...when used topically and appropriately (6155).
PREGNANCY AND LACTATION:
There is insufficient reliable information available about the safety of tyrosine during pregnancy and lactation when used in medicinal amounts.
Some pharmacokinetic research shows that taking a single dose of tyrosine 2-10 grams orally can modestly increase levels of free tyrosine in breast milk. However, total levels are not affected, and levels remain within the range found in infant formulas. Therefore, it is not clear if the increase in free tyrosine is a concern (91467).
LIKELY SAFE ...when used orally, topically, intravenously, intramuscularly, or intranasally and appropriately. Vitamin B12 is generally considered safe, even in large doses (15,1344,1345,1346,1347,1348,2909,6243,7289,7881)(9414,9416,10126,14392,15765,82832,82949,82860,82864,90386)(111334,111551).
PREGNANCY: LIKELY SAFE
when used orally in amounts that do not exceed the recommended dietary allowance (RDA).
The RDA for vitamin B12 during pregnancy is 2.6 mcg daily (6243). There is insufficient reliable information available about the safety of larger amounts of vitamin B12 during pregnancy.
LACTATION: LIKELY SAFE
when used orally in amounts that do not exceed the recommended dietary allowance (RDA).
The RDA of vitamin B12 during lactation is 2.8 mcg daily (6243). There is insufficient reliable information available about the safety of larger amounts of vitamin B12 while breastfeeding.
LIKELY SAFE ...when used orally and appropriately in doses that do not exceed the tolerable upper intake level (UL) of 100 mg daily in the form of pyridoxine for adults (15,6243). ...when used parenterally and appropriately. Injectable vitamin B6 (pyridoxine) is an FDA-approved prescription product (15).
POSSIBLY SAFE ...when used orally and appropriately in doses of 101-200 mg daily (6243,8558).
POSSIBLY UNSAFE ...when used orally in doses at or above 500 mg daily. High doses, especially those exceeding 1000 mg daily or total doses of 1000 grams or more, pose the most risk. However, neuropathy can occur with lower daily or total doses (6243,8195). ...when used intramuscularly in high doses and frequency due to potential for rhabdomyolysis (90795).
CHILDREN: LIKELY SAFE
when used orally and appropriately in doses that do not exceed the tolerable upper intake level (UL) of vitamin B6 in the form of pyridoxine 30 mg daily for children aged 1-3 years, 40 mg daily for 4-8 years, 60 mg daily for 9-13 years, and 80 mg daily for 14-18 years (6243).
CHILDREN: POSSIBLY SAFE
when used orally and appropriately in amounts exceeding the recommended dietary allowance (5049,8579,107124,107125,107135).
CHILDREN: POSSIBLY UNSAFE
when used orally in excessive doses, long-term (6243).
PREGNANCY: LIKELY SAFE
when used orally and appropriately.
A special sustained-release product providing vitamin B6 (pyridoxine) 75 mg daily is FDA-approved for use in pregnancy. Vitamin B6 (pyridoxine) is also considered a first-line treatment for nausea and vomiting in pregnancy by the American College of Obstetrics and Gynecology (111601). However, it should not be used long-term or without medical supervision and close monitoring. The tolerable upper intake level (UL) refers to vitamin B6 in the form of pyridoxine and is 80 mg daily for those aged 14-18 years and 100 mg daily for 19 years and older (6243).
PREGNANCY: POSSIBLY UNSAFE
when used orally in excessive doses.
There is some concern that high-dose maternal vitamin B6 (pyridoxine) can cause neonatal seizures (4609,6397,8197).
LACTATION: LIKELY SAFE
when used orally in doses not exceeding the tolerable upper intake level (UL) of vitamin B6 in the form of pyridoxine 80 mg daily for those aged 14-18 years and 100 mg daily for those 19 years and older.
The recommended dietary allowance (RDA) in lactating women is 2 mg daily (6243). There is insufficient reliable information available about the safety of vitamin B6 when used in higher doses in breast-feeding women.
LIKELY SAFE ...when used orally, topically, intramuscularly, or intravenously and appropriately. Vitamin C is safe when taken orally in doses below the tolerable upper intake level (UL). Tell patients not to exceed the UL of 2000 mg daily (1959,4713,4714,4844). ...when used intravenously or intramuscularly and appropriately. Injectable vitamin C is an FDA-approved prescription product (15) and has been used with apparent safety in clinical trials up to 150 mg/kg daily for up to 4 days (114489) and up to 200 mg/kg daily for up to 2 days (114492).
POSSIBLY UNSAFE ...when used orally in excessive doses. Doses greater than the tolerable upper intake level (UL) of 2000 mg daily can significantly increase the risk of adverse effects such as osmotic diarrhea and gastrointestinal upset (4844).
CHILDREN: LIKELY SAFE
when used orally and appropriately (4844,10352,14443).
CHILDREN: POSSIBLY UNSAFE
when used orally in excessive amounts.
Tell patients not to use doses above the tolerable upper intake level (UL) of 400 mg daily for children ages 1 to 3 years, 650 mg daily for children 4 to 8 years, 1200 mg daily for children 9 to 13 years, and 1800 mg daily for adolescents 14 to 18 years. Higher doses can cause osmotic diarrhea and gastrointestinal upset (4844).
PREGNANCY AND LACTATION: LIKELY SAFE
when used orally and appropriately (4844).
PREGNANCY AND LACTATION: POSSIBLY UNSAFE
when used orally in excessive doses.
Tell patients over age 19 not to use doses exceeding the UL of 2000 mg daily when pregnant or breast-feeding and for those 14-18 years of age not to use doses exceeding 1800 mg daily when pregnant or breast-feeding. Higher doses can cause osmotic diarrhea and gastrointestinal upset. Large doses of vitamin C during pregnancy can also cause newborn scurvy (4844); avoid using.
Below is general information about the interactions of the known ingredients contained in the product C4 Ripped Icy Blue Razz. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
Theoretically, caffeine might decrease the vasodilatory effects of adenosine and interfere with its use prior to stress testing.
 Details
Some evidence shows that caffeine is a competitive inhibitor of adenosine and can reduce the vasodilatory effects of adenosine in humans (38172). However, other research shows that caffeine does not seem to affect supplemental adenosine because high interstitial levels of adenosine overcome the antagonistic effects of caffeine (11771). It is recommended that methylxanthines and methylxanthine-containing products be stopped 24 hours prior to pharmacological stress tests (11770). However, methylxanthines appear more likely to interfere with dipyridamole (Persantine) than adenosine-induced stress testing (11771).
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Theoretically, concomitant use might increase levels and adverse effects of caffeine.
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Alcohol reduces caffeine metabolism. Concomitant use of alcohol can increase caffeine serum concentrations and the risk of caffeine adverse effects (6370).
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Theoretically, caffeine may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
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Theoretically, taking caffeine with antidiabetes drugs might interfere with blood glucose control.
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Theoretically, large amounts of caffeine might increase the cardiac inotropic effects of beta-agonists (15).
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Theoretically, caffeine might reduce the effects of carbamazepine and increase the risk for convulsions.
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Animal research suggests that taking caffeine can lower the anticonvulsant effects of carbamazepine and can induce seizures when taken in doses above 400 mg/kg (23559,23561). Human research has shown that taking caffeine 300 mg in three divided doses along with carbamazepine 200 mg reduces the bioavailability of carbamazepine by 32% and prolongs the plasma half-life of carbamazepine 2-fold in healthy individuals (23562).
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Theoretically, cimetidine might increase the levels and adverse effects of caffeine.
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Cimetidine decreases the rate of caffeine clearance by 31% to 42% (11736).
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Caffeine might increase the levels and adverse effects of clozapine and acutely exacerbate psychotic symptoms.
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Caffeine might increase the effects and toxicity of clozapine. Caffeine doses of 400-1000 mg per day inhibit clozapine metabolism (5051). Clozapine is metabolized by cytochrome P450 1A2 (CYP1A2). Although researchers speculate that caffeine might inhibit CYP1A2, there is no reliable evidence that caffeine affects CYP1A2. There is also speculation that genetic factors might make some patients more sensitive to an interaction between clozapine and caffeine (13741). In one case report, severe, life-threatening clozapine toxicity and multiorgan system failure occurred in a patient with schizophrenia stabilized on clozapine who consumed caffeine 600 mg daily (108817).
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Theoretically, contraceptive drugs might increase the levels and adverse effects of caffeine.
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Theoretically, concomitant use might increase the levels and adverse effects of caffeine.
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Theoretically, caffeine might decrease the vasodilatory effects of dipyridamole and interfere with its use prior to stress testing.
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Caffeine inhibits dipyridamole-induced vasodilation (11770,11772). It is recommended that methylxanthines and methylxanthine-containing products be stopped 24 hours prior to pharmacological stress tests (11770). Methylxanthines appear more likely to interfere with dipyridamole (Persantine) than adenosine-induced stress testing (11771).
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Theoretically, disulfiram use might increase the levels and adverse effects of caffeine.
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Disulfiram decreases the rate of caffeine clearance (11840).
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Theoretically, using caffeine with diuretic drugs might increase the risk of hypokalemia.
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Theoretically, concomitant use might increase the risk for stimulant adverse effects.
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Use of ephedrine with caffeine can increase the risk of stimulatory adverse effects. There is evidence that using ephedrine with caffeine might increase the risk of serious life-threatening or debilitating adverse effects such as hypertension, myocardial infarction, stroke, seizures, and death (1275,6486,10307).
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Theoretically, estrogens might increase the levels and adverse effects of caffeine.
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Theoretically, caffeine might reduce the effects of ethosuximide and increase the risk for convulsions.
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Animal research suggests that caffeine 92.4 mg/kg can decrease the anticonvulsant activity of ethosuximide (23560). However, this effect has not been reported in humans.
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Theoretically, caffeine might reduce the effects of felbamate and increase the risk for convulsions.
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Animal research suggests that a high dose of caffeine 161.7 mg/kg can decreases the anticonvulsant activity of felbamate (23563). However, this effect has not been reported in humans.
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Theoretically, fluconazole might increase the levels and adverse effects of caffeine.
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Fluconazole decreases caffeine clearance by approximately 25% (11022).
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Theoretically, caffeine might increase the levels and adverse effects of flutamide.
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In vitro evidence suggests that caffeine can inhibit the metabolism of flutamide (23553). However, this effect has not been reported in humans.
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Theoretically, fluvoxamine might increase the levels and adverse effects of caffeine.
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Fluvoxamine reduces caffeine metabolism (6370).
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Abrupt caffeine withdrawal might increase the levels and adverse effects of lithium.
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Caffeine has diuretic activity. When abruptly discontinued, caffeine may alter the clearance of lithium (609). There are two case reports of lithium tremor that worsened upon abrupt coffee withdrawal (610) and 6 case reports of elevated serum lithium levels after reducing or eliminating caffeine intake (114665). In one case, a male with schizoaffective disorder stabilized on lithium had an elevated lithium level after reducing his caffeine intake by 87%. At a later date, he increased his caffeine intake by 6-fold, resulting in a subtherapeutic lithium level and a recurrence of psychiatric symptoms (114665).
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Theoretically, metformin might increase the levels and adverse effects of caffeine.
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Animal research suggests that metformin can reduce caffeine metabolism (23571). However, this effect has not been reported in humans.
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Theoretically, methoxsalen might increase the levels and adverse effects of caffeine.
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Methoxsalen reduces caffeine metabolism (23572).
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Theoretically, mexiletine might increase the levels and adverse effects of caffeine.
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Theoretically, concomitant use might increase the risk of a hypertensive crisis.
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Caffeine has been shown to inhibit monoamine oxidase (MAO) A and B in laboratory studies (37724,37877,37912,38108). Concomitant intake of large amounts of caffeine with MAOIs might precipitate a hypertensive crisis (15). In a case report, a patient that consumed 10-12 cups of caffeinated coffee and took the MAOI tranylcypromine presented with severe hypertension (91086). Hypertension was resolved after the patient switched to drinking decaffeinated coffee.
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Theoretically, concomitant use might increase the risk of hypertension.
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Concomitant use of caffeine and nicotine has been shown to have additive cardiovascular effects, including increased heart rate and blood pressure. Blood pressure was increased by 10.8/12.4 mmHg when the agents were used concomitantly (36549).
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Theoretically, caffeine might decrease the effects of pentobarbital.
Details
Caffeine might negate the hypnotic effects of pentobarbital (13742).
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Theoretically, caffeine might reduce the effects of phenobarbital and increase the risk for convulsions.
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Theoretically, phenothiazines might increase the levels and adverse effects of caffeine.
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Theoretically, phenylpropanolamine might increase the risk of hypertension, as well as the levels and adverse effects of caffeine.
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Theoretically, caffeine might reduce the effects of phenytoin and increase the risk for convulsions.
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Theoretically, caffeine might increase the levels and clinical effects of pioglitazone.
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Animal research suggests that caffeine can modestly increase the maximum concentration, area under the curve, and half-life of pioglitazone, and also reduce its clearance. This increased the antidiabetic effects of pioglitazone (108812). However, the exact mechanism of this interaction is unclear.
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Theoretically, quinolone antibiotics might increase the levels and adverse effects of caffeine.
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Theoretically, concomitant use might increase the levels and adverse effects of both caffeine and riluzole.
Details
Caffeine and riluzole are both metabolized by cytochrome P450 1A2 (CYP1A2), and concomitant use might reduce the metabolism of one or both agents (11739).
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Theoretically, concomitant use might increase stimulant adverse effects.
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Due to the central nervous system (CNS) stimulant effects of caffeine, concomitant use with stimulant drugs can increase the risk of adverse effects (11832).
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Theoretically, terbinafine might increase the levels and adverse effects of caffeine.
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Terbinafine decreases the clearance of intravenous caffeine by 19% (11740).
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Theoretically, caffeine might increase the levels and adverse effects of theophylline.
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Large amounts of caffeine might inhibit theophylline metabolism (11741).
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Theoretically, caffeine might increase the levels and adverse effects of tiagabine.
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Animal research suggests that chronic caffeine administration can increase the serum concentrations of tiagabine. However, concomitant use does not seem to reduce the antiepileptic effects of tiagabine (23561).
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Theoretically, ticlopidine might increase the levels and adverse effects of caffeine.
Details
In vitro evidence suggests that ticlopidine can inhibit caffeine metabolism (23557). However, this effect has not been reported in humans.
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Theoretically, caffeine might reduce the effects of valproate and increase the risk for convulsions.
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Theoretically, verapamil might increase the levels and adverse effects of caffeine.
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Verapamil increases plasma caffeine concentrations by 25% (11741).
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Calcium citrate might increase aluminum absorption and toxicity. Other types of calcium do not increase aluminum absorption.
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Calcium citrate can increase the absorption of aluminum when taken with aluminum hydroxide. The increase in aluminum levels may become toxic, particularly in individuals with kidney disease (21631). However, the effect of calcium citrate on aluminum absorption is due to the citrate anion rather than calcium cation. Calcium acetate does not appear to increase aluminum absorption (93006).
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Calcium reduces the absorption of bisphosphonates.
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Advise patients to take bisphosphonates at least 30 minutes before calcium, but preferably at a different time of day. Calcium supplements decrease absorption of bisphosphonates (12937).
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Taking calcipotriene with calcium might increase the risk for hypercalcemia.
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Calcipotriene is a vitamin D analog used topically for psoriasis. It can be absorbed in sufficient amounts to cause systemic effects, including hypercalcemia (12938). Theoretically, combining calcipotriene with calcium supplements might increase the risk of hypercalcemia.
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Intravenous calcium may decrease the effects of calcium channel blockers; oral calcium is unlikely to have this effect.
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Intravenous calcium is used to decrease the effects of calcium channel blockers in the management of overdose. Intravenous calcium gluconate has been used before intravenous verapamil (Isoptin) to prevent or reduce the hypotensive effects without affecting the antiarrhythmic effects (6124). But there is no evidence that dietary or supplemental calcium when taken orally interacts with calcium channel blockers (12939,12947).
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Co-administration of intravenous calcium and ceftriaxone can result in precipitation of a ceftriaxone-calcium salt in the lungs and kidneys.
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Avoid administering intravenous calcium in any form, such as parenteral nutrition or Lactated Ringers, within 48 hours of intravenous ceftriaxone. Case reports in neonates show that administering intravenous ceftriaxone and calcium can result in precipitation of a ceftriaxone-calcium salt in the lungs and kidneys. In several cases, neonates have died as a result of this interaction (15794,21632). So far there are no reports in adults; however, there is still concern that this interaction might occur in adults.
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Using intravenous calcium with digoxin might increase the risk of fatal cardiac arrhythmias.
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Theoretically, calcium may reduce the therapeutic effects of diltiazem.
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Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation (10574). Theoretically, calcium might increase this risk of hypercalcemia and reduce the effectiveness of diltiazem.
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Calcium seems to reduce levels of dolutegravir.
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Advise patients to take dolutegravir either 2 hours before or 6 hours after taking calcium supplements. Pharmacokinetic research suggests that taking calcium carbonate 1200 mg concomitantly with dolutegravir 50 mg reduces plasma levels of dolutegravir by almost 40%. Calcium appears to decrease levels of dolutegravir through chelation (93578).
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Calcium seems to reduce levels of elvitegravir.
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Advise patients to take elvitegravir either 2 hours before or 2 hours after taking calcium supplements. Pharmacokinetic research suggests that taking calcium along with elvitegravir can reduce blood levels of elvitegravir through chelation (94166).
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Calcium seems to reduce the absorption and effectiveness of levothyroxine.
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Theoretically, concomitant use of calcium and lithium may increase this risk of hypercalcemia.
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Clinical research suggests that long-term use of lithium may cause hypercalcemia in 10% to 60% of patients (38953). Theoretically, concomitant use of lithium and calcium supplements may further increase this risk.
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Calcium seems to reduce the absorption of quinolone antibiotics.
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Calcium may reduce levels of raltegravir.
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Pharmacokinetic research shows that taking a single dose of calcium carbonate 3000 mg along with raltegravir 400 mg twice daily modestly decreases the mean area under the curve of raltegravir, but the decrease does not necessitate a dose adjustment of raltegravir (94164). However, a case of elevated HIV-1 RNA levels and documented resistance to raltegravir has been reported for a patient taking calcium carbonate 1 gram three times daily plus vitamin D3 (cholecalciferol) 400 IU three times daily in combination with raltegravir 400 mg twice daily for 11 months. It is thought that calcium reduced raltegravir levels by chelation, leading to treatment failure (94165).
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Calcium seems to reduce the absorption of sotalol.
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Advise patients to separate doses by at least 2 hours before or 4-6 hours after calcium. Calcium appears to reduce the absorption of sotalol, probably by forming insoluble complexes (10018).
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Calcium seems to reduce the absorption of tetracycline antibiotics.
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Advise patients to take oral tetracyclines at least 2 hours before, or 4-6 hours after calcium supplements. Taking calcium at the same time as oral tetracyclines can reduce tetracycline absorption. Calcium binds to tetracyclines in the gut (1843).
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Taking calcium along with thiazides might increase the risk of hypercalcemia and renal failure.
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Thiazides reduce calcium excretion by the kidneys (1902). Using thiazides along with moderately large amounts of calcium carbonate increases the risk of milk-alkali syndrome (hypercalcemia, metabolic alkalosis, renal failure). Patients may need to have their serum calcium levels and/or parathyroid function monitored regularly.
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Theoretically, calcium may reduce the therapeutic effects of verapamil.
Details
Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation (10574). Theoretically, use of calcium supplements may increase this risk of hypercalcemia and reduce the effectiveness of verapamil.
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Theoretically, using topical capsaicin may increase the risk of ACE inhibitor-induced cough.
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There is one case report of a topically applied capsaicin cream contributing to the cough reflex in a patient using an ACEI (12414). However, it is unclear if this interaction is clinically significant.
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Theoretically, capsicum may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
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In vitro research shows that capsicum might increase the effects of antiplatelet drugs (12406,12407). Also, population research shows that capsicum is associated with an increased risk of self-reported bleeding in patients taking warfarin (12405,20348). However, clinical research shows that taking a single dose of capsaicin (Asian Herbex Ltd.), the active ingredient in capsicum, 400-800 mcg orally in combination with aspirin 500 mg does not decrease platelet aggregation when compared with taking aspirin 500 mg alone. Also, there was no notable effect on measures of platelet aggregation with capsaicin (92990). It is unclear whether capsaicin must be used in more than a single dose to affect platelet aggregation.
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Theoretically, taking capsicum with antidiabetes drugs might increase the risk of hypoglycemia.
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Preliminary clinical research shows that consuming capsicum 5 grams along with a glucose drink attenuates the rise in plasma glucose after 30 minutes by 21%, decreases the 2-hour postprandial area under the curve of plasma glucose by 11%, and increases the 2-hour postprandial area under the curve of plasma insulin by 58% in healthy individuals when compared with placebo (40453,40614). Other clinical research shows that taking capsicum 5 mg daily for 28 days significantly reduces postprandial blood glucose and insulin levels, but not fasting blood glucose and insulin levels, in patients with gestational diabetes (96457).
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Theoretically, taking capsicum with aspirin might reduce the bioavailability of aspirin.
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Animal research shows that acute or chronic intake of capsicum pepper reduces oral aspirin bioavailability (22617). This has not been shown in humans.
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Theoretically, taking capsicum with ciprofloxacin might increase levels and adverse effects of ciprofloxacin.
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Animal research shows that concomitant use of capsaicin, the active constituent of capsicum, and ciprofloxacin increases the bioavailability of ciprofloxacin by up to 70% (22613).
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Theoretically, taking capsicum with theophylline might increase the levels and adverse effects of theophylline.
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Theoretically, concomitant use of coleus and anticoagulant or antiplatelet drugs might increase the risk of bruising and bleeding.
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Theoretically, combining coleus with antihypertensive drugs might cause additive blood pressure lowering effects and increase the risk of hypotension.
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Theoretically, combining coleus with calcium channel blockers might increase the coronary vasodilatory effects.
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Theoretically, taking coleus may affect drugs metabolized by CYP2C9 and increase the risk of adverse effects or reduce the effectiveness.
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Research on the effect of coleus on CYP2C9 is conflicting. Some animal research shows that coleus extract can induce CYP2C9, while in vitro research shows that coleus can inhibit CYP2C9 (91891). Until more is known, advise patients that taking coleus might increase or decrease levels of drugs metabolized by CYP2C9.
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Theoretically, taking coleus might decrease serum levels of drugs metabolized by CYP3A4.
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In vitro research shows that coleus can activate the nuclear receptor, pregnane X receptor (PXR), which results in increased expression of CYP3A4 (44399,44412). Although the clinical significance of this is not known, use caution when considering concomitant use of coleus and other drugs affected by these enzymes.
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Theoretically, combining coleus with nitrates might increase the coronary vasodilatory effects.
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Theoretically, taking coleus may affect the metabolism of warfarin and increase the risk of adverse effects or reduce the effectiveness.
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Some animal research shows that coleus extract can induce cytochrome P450 2C9 (CYP2C9), an enzyme that metabolizes warfarin. However, other in vitro research shows that coleus can inhibit CYP2C9 (91891). Theoretically, taking coleus with drugs metabolized by CYP2C9 might affect drug levels and the risk of adverse effects. Until more is known, advise patients that taking coleus might increase or decrease levels of warfarin.
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Theoretically, concomitant use of cowhage and anesthesia might increase the risk of arrhythmias.
Details
Cowhage contains levodopa (7020,7205,46334,46336,94723,94724). Use of levodopa with cyclopropane or halogenated hydrocarbon anesthesia has led to arrhythmias. Other anesthetics have not been implicated (15). Use other anesthetics in patients taking cowhage or tell patients to stop taking cowhage at least 2 weeks before surgery.
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Theoretically, concomitant use of cowhage and antidiabetes drugs might increase the risk of hypoglycemia.
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Animal research shows that cowhage might have hypoglycemic effects (7221).
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Theoretically, use of cowhage might decrease the clinical effects of antipsychotic drugs.
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Theoretically, concomitant use of cowhage and guanethidine might increase the risk of hypotension.
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Concomitant use can increase the risk of levodopa-related adverse effects.
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Theoretically, concomitant use of cowhage and methyldopa might increase the risk of hypotension.
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Theoretically, concomitant use of cowhage and non-selective MAOIs might increase the risk of hypertensive crisis.
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Theoretically, use of TCAs might reduce the levels and clinical effects of cowhage.
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Theoretically, high doses of folic acid might increase the toxicity of 5-fluorouracil.
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Increases in gastrointestinal side effects of 5-fluorouracil, such as stomatitis and diarrhea, have been described in two clinical studies when leucovorin, a form of folic acid, was administered with 5-fluorouracil (16845).
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Use of high-dose folic acid might contribute to capecitabine toxicity.
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Clinical research suggests that higher serum folate levels are associated with an increased risk for moderate or severe toxicity during capecitabine-based treatment for colorectal cancer (105402). Additionally, in one case report, taking folic acid 15 mg daily might have contributed to increased toxicity, including severe diarrhea, vomiting, edema, hand-foot syndrome, and eventually death, in a patient prescribed capecitabine (16837).
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Folic acid might reduce the efficacy of methotrexate as a cancer treatment when given concurrently.
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Methotrexate exerts its cytotoxic effects by preventing conversion of folic acid to the active form needed by cells. There is some evidence that folic acid supplements reduce the efficacy of methotrexate in the treatment of acute lymphoblastic leukemia, and theoretically they could reduce its efficacy in the treatment of other cancers (9420). Advise cancer patients to consult their oncologist before using folic acid supplements. In patients treated with long-term, low-dose methotrexate for rheumatoid arthritis (RA) or psoriasis, folic acid supplements can reduce the incidence of side effects, without reducing efficacy (768,2162,4492,4493,4494,4546,9369).
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Folic acid might have antagonistic effects on phenobarbital and increase the risk for seizures.
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Folic acid might reduce serum levels of phenytoin in some patients.
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Folic acid may be a cofactor in phenytoin metabolism (4471). Folic acid, in doses of 1 mg daily or more, can reduce serum levels of phenytoin in some patients (4471,4477,4531,4536). Increases in seizure frequency have been reported. If folic acid supplements are added to established phenytoin therapy, monitor serum phenytoin levels closely. If phenytoin and folic acid are started at the same time and continued together, adverse changes in phenytoin pharmacokinetics are avoided (4471,4472,4473,4531). Note that phenytoin also reduces serum folate levels.
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Folic acid might have antagonistic effects on primidone and increase the risk for seizures.
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Folic acid might antagonize the effects of pyrimethamine.
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Folic acid can antagonize the antiparasitic effects of pyrimethamine against toxoplasmosis and Pneumocystis carinii pneumonia. Folic acid doesn't antagonize the effects of pyrimethamine in the treatment of malaria, because malarial parasites cannot use exogenous folic acid. Use folinic acid as an alternative to folic acid when indicated (9380).
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Theoretically, green coffee might decrease the vasodilatory effects of adenosine and interfere with its use prior to stress testing.
Details
Green coffee can contain caffeine. Caffeine is a competitive inhibitor of adenosine at the cellular level. However, caffeine does not seem to affect supplemental adenosine because high interstitial levels of adenosine overcome the antagonistic effects of caffeine (11771). It is recommended that methylxanthines such as caffeine, as well as methylxanthine-containing products, be stopped 24 hours prior to pharmacological stress tests (11770). However, methylxanthines appear more likely to interfere with dipyridamole (Persantine) than adenosine-induced stress testing (11771).
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Theoretically, alcohol might increase the levels and adverse effects of caffeine.
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Theoretically, green coffee may decrease the levels and effects of alendronate.
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In human research, drinking coffee with alendronate reduces the bioavailability of alendronate by 60% (11735). Whether green coffee reduces the bioavailability of alendronate has not been investigated. Separate green coffee ingestion and alendronate administration by two hours.
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Theoretically, green coffee may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
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Green coffee can contain caffeine. Caffeine is reported to have antiplatelet activity (8028,8029). Theoretically, caffeine in green coffee might increase the risk of bleeding when used concomitantly with these agents. However, this interaction has not been reported in humans. There is some evidence that caffeinated coffee might increase the fibrinolytic activity in blood (8030).
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Theoretically, taking green coffee and antidiabetes drugs might interfere with blood glucose control.
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Theoretically, taking green coffee with antihypertensive drugs might increase the risk of hypotension.
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Theoretically, concomitant use of large amounts of green coffee might increase cardiac inotropic effects of beta-agonists.
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Green coffee can contain caffeine. Caffeine can increase cardiac inotropic effects of beta-agonists (15).
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Theoretically, cimetidine might increase the effects and adverse effects of caffeine in green coffee.
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Theoretically, green coffee might increase the levels and adverse effects of clozapine and acutely exacerbate psychotic symptoms.
Details
Green coffee can contain caffeine. Caffeine can increase the effects and toxicity of clozapine. Caffeine doses of 400-1000 mg daily inhibit clozapine metabolism (5051). Clozapine is metabolized by cytochrome P450 1A2 (CYP1A2). Researchers speculate that caffeine might inhibit CYP1A2. However, there is no reliable evidence that caffeine affects CYP1A2. There is also speculation that genetic factors might make some patients more sensitive to an interaction between clozapine and caffeine (13741).
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Theoretically, concomitant use might increase the effects and adverse effects of caffeine found in green coffee.
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Theoretically, green coffee might decrease the vasodilatory effects of dipyridamole and interfere with its use prior to stress testing.
Details
Green coffee can contain caffeine. Caffeine is a methylxanthine that may inhibit dipyridamole-induced vasodilation (11770,11772,24974,37985,53795). It is recommended that methylxanthines such as caffeine, as well as methylxanthine-containing products such as green coffee, be stopped 24 hours prior to pharmacological stress tests (11770). Methylxanthines appear more likely to interfere with dipyridamole (Persantine) than adenosine-induced stress testing (11771).
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Theoretically, disulfiram might increase the levels and adverse effects of caffeine.
Details
Green coffee can contain caffeine. In human research, disulfiram decreases the clearance and increases the half-life of caffeine (11840).
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Theoretically, concomitant use might increase the risk of hypokalemia.
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Theoretically, concomitant use might increase the risk of stimulant adverse effects.
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Green coffee can contain caffeine. There is evidence that using ephedrine with caffeine might increase the risk of serious life-threatening or debilitating adverse effects such as hypertension, myocardial infarction, stroke, seizures, and death (1275,6486,9740,10307). Tell patients to avoid taking caffeine with ephedrine and other stimulants.
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Theoretically, estrogens might increase the levels and adverse effects of caffeine.
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Green coffee can contain caffeine. Estrogen inhibits caffeine metabolism (2714).
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Theoretically, fluconazole might increase the levels and adverse effects of caffeine.
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Theoretically, fluvoxamine might increase the levels and adverse effects of caffeine.
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Theoretically, abrupt green coffee withdrawal might increase the levels and adverse effects of lithium.
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Theoretically, mexiletine might increase the levels and adverse effects of caffeine.
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Theoretically, concomitant use might increase the risk of a hypertensive crisis.
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Theoretically, concomitant use might increase the risk of hypertension.
Details
Green coffee can contain caffeine. Concomitant use of caffeine and nicotine has been shown to have additive cardiovascular effects, including increased heart rate and blood pressure. Blood pressure was increased by 10.8/12.4 mmHg when the agents were used concomitantly (36549).
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Theoretically, green coffee might reduce the effects of pentobarbital.
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Green coffee can contain caffeine. Theoretically, caffeine might negate the hypnotic effects of pentobarbital (13742).
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Theoretically, phenothiazines might increase the levels and adverse effects of caffeine.
Details
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Theoretically, phenylpropanolamine might increase the risk of hypertension, as well as the levels and adverse effects of caffeine.
Details
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Theoretically, caffeine might increase the levels and clinical effects of pioglitazone.
Details
Green coffee contains caffeine. Animal research suggests that caffeine can modestly increase the maximum concentration, area under the curve, and half-life of pioglitazone, and also reduce its clearance. This increased the antidiabetic effects of pioglitazone (108812). However, the exact mechanism of this interaction is unclear.
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Theoretically, quinolone antibiotics might increase the levels and adverse effects of caffeine.
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Theoretically, concomitant use might increase the levels and adverse effects of both caffeine and riluzole.
Details
Green coffee can contain caffeine. Caffeine and riluzole are both metabolized by cytochrome P450 1A2 (CYP1A2), and concomitant use might reduce metabolism of one or both agents (11739).
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Theoretically, concomitant use might increase stimulant adverse effects.
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Green coffee can contain caffeine. Due to the central nervous system (CNS) stimulant effects of caffeine, concomitant use with stimulant drugs can increase the risk of adverse effects (11832).
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Theoretically, terbinafine might increase the levels and adverse effects of caffeine.
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Green coffee can contain caffeine. Terbinafine decreases the clearance of intravenous caffeine by 19% (11740).
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Theoretically, green coffee might increase the levels and adverse effects of theophylline.
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Green coffee can contain caffeine. Large amounts of caffeine might inhibit theophylline metabolism (11741).
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Theoretically, concomitant use might increase the levels and adverse effects of caffeine.
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Green coffee can contain caffeine. Verapamil increases plasma caffeine concentrations by 25% (11741).
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Theoretically, L-carnitine might increase the anticoagulant effects of acenocoumarol.
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L-carnitine might enhance the anticoagulant effects of acenocoumarol, an oral anticoagulant similar to warfarin, but shorter-acting (9878,12165). There are at least two case reports of INR elevation with concomitant use. In one case, a 33-year-old male with a previously stable INR had an elevated INR of 4.65 after L-carnitine was started and continued for 10 weeks. INR normalized after discontinuation of the L-carnitine-containing product (12165).
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Theoretically, L-carnitine might decrease the effectiveness of thyroid hormone replacement.
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Theoretically, L-carnitine might increase the anticoagulant effects of warfarin.
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Theoretically, niacinamide may have additive effects when used with anticoagulant or antiplatelet drugs, especially in patients on hemodialysis.
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Niacinamide might increase the levels and adverse effects of carbamazepine.
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Plasma levels of carbamazepine were increased in two children given high-dose niacinamide, 60-80 mg/kg/day. This might be due to inhibition of the cytochrome P450 enzymes involved in carbamazepine metabolism (14506). There is not enough data to determine the clinical significance of this interaction.
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Niacinamide might increase the levels and adverse effects of primidone.
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Case reports in children suggest niacinamide 60-100 mg/kg/day reduces hepatic metabolism of primidone to phenobarbital, and reduces the overall clearance rate of primidone (14506); however, there is not enough data to determine the clinical significance of this potential interaction.
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Theoretically, tyrosine might decrease the effectiveness of levodopa.
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Tyrosine and levodopa compete for absorption in the proximal duodenum by the large neutral amino acid (LNAA) transport system (2719). Advise patients to separate doses of tyrosine and levodopa by at least 2 hours.
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Theoretically, tyrosine might have additive effects with thyroid hormone medications.
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Tyrosine is a precursor to thyroxine and might increase levels of thyroid hormones (7212).
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Theoretically, vitamin B6 might increase the photosensitivity caused by amiodarone.
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Theoretically, vitamin B6 may have additive effects when used with antihypertensive drugs.
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Research in hypertensive rats shows that vitamin B6 can decrease systolic blood pressure (30859,82959,83093). Similarly, clinical research in patients with hypertension shows that taking high doses of vitamin B6 may reduce systolic and diastolic blood pressure, possibly by reducing plasma levels of epinephrine and norepinephrine (83091).
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Vitamin B6 may increase the metabolism of levodopa when taken alone, but not when taken in conjunction with carbidopa.
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Vitamin B6 (pyridoxine) enhances the metabolism of levodopa, reducing its clinical effects. However, this interaction does not occur when carbidopa is used concurrently with levodopa (Sinemet). Therefore, it is not likely to be a problem in most people (3046).
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High doses of vitamin B6 may reduce the levels and clinical effects of phenobarbital.
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High doses of vitamin B6 may reduce the levels and clinical effects of phenytoin.
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High-dose vitamin C might slightly prolong the clearance of acetaminophen.
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A small pharmacokinetic study in healthy volunteers shows that taking high-dose vitamin C (3 grams) 1.5 hours after taking acetaminophen 1 gram slightly increases the apparent half-life of acetaminophen from around 2.3 hours to 3.1 hours. Ascorbic acid competitively inhibits sulfate conjugation of acetaminophen. However, to compensate, elimination of acetaminophen glucuronide and unconjugated acetaminophen increases (6451). This effect is not likely to be clinically significant.
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Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
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The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs that generate free radicals, such as cyclophosphamide, chlorambucil, carmustine, busulfan, and thiotepa (391). In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells (14012,14013). More evidence is needed to determine what effect, if any, antioxidants such as vitamin C have on chemotherapy.
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Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
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Research in animals and humans shows that vitamin C increases aluminum absorption, theoretically by chelating aluminum and keeping it in solution where it is available for absorption (10549,10550,10551,21556). In people with normal renal function, urinary excretion of aluminum will likely increase, making aluminum retention and toxicity unlikely (10549). Patients with renal failure who take aluminum-containing compounds such as phosphate binders should avoid vitamin C supplements in doses above the recommended dietary allowances.
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Theoretically, the antioxidant effects of vitamin C might reduce the effectiveness of antitumor antibiotics.
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The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs which generate free radicals, such as doxorubicin (391). In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells (14012,14013). More evidence is needed to determine what effects, if any, antioxidants such as vitamin C have on chemotherapy.
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Acidification of the urine by vitamin C might increase aspirin levels.
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It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels (3046). However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion (10588,10589), suggesting this interaction is not clinically significant.
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Acidification of the urine by vitamin C might increase choline magnesium trisalicylate levels.
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It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels (3046,4531). However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion (10588,10589), suggesting this interaction probably is not clinically significant.
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Vitamin C might increase blood levels of estrogens.
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Increases in plasma estrogen levels of up to 55% occur under some circumstances when vitamin C is taken concurrently with oral contraceptives or hormone replacement therapy, including topical products (129,130,11161). It is suggested that vitamin C prevents oxidation of estrogen in the tissues, regenerates oxidized estrogen, and reduces sulfate conjugation of estrogen in the gut wall (129,11161). When tissue levels of vitamin C are high, these processes are already maximized and supplemental vitamin C does not have any effect on estrogen levels. Increases in plasma estrogen levels may occur when patients who are deficient in vitamin C take supplements (11161). Monitor these patients for estrogen-related side effects.
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Theoretically, vitamin C might decrease levels of fluphenazine.
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In one patient there was a clinically significant decrease in fluphenazine levels when vitamin C (500 mg twice daily) was started (11017). The mechanism is not known, and there is no further data to confirm this interaction.
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Vitamin C can modestly reduce indinavir levels.
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One pharmacokinetic study shows that taking vitamin C 1 gram orally once daily along with indinavir 800 mg orally three times daily reduces the area under the concentration-time curve of indinavir by 14%. The mechanism of this interaction is unknown, but it is unlikely to be clinically significant in most patients. The effect of higher doses of vitamin C on indinavir levels is unknown (11300,93578).
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Vitamin C can increase levothyroxine absorption.
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Two clinical studies in adults with poorly controlled hypothyroidism show that swallowing levothyroxine with a glass of water containing vitamin C 500-1000 mg in solution reduces thyroid stimulating hormone (TSH) levels and increases thyroxine (T4) levels when compared with taking levothyroxine alone. This suggests that vitamin C increases the oral absorption of levothyroxine, possibly due to a reduction in pH (102978).
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Vitamin C might decrease the beneficial effects of niacin on high-density lipoprotein (HDL) cholesterol levels.
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A combination of niacin and simvastatin (Zocor) effectively raises HDL cholesterol levels in patients with coronary disease and low HDL levels. Clinical research shows that taking a combination of antioxidants (vitamin C, vitamin E, beta-carotene, and selenium) along with niacin and simvastatin (Zocor) attenuates this rise in HDL, specifically the HDL-2 and apolipoprotein A1 fractions, by more than 50% in patients with coronary disease (7388,11537). It is not known whether this adverse effect is due to a single antioxidant such as vitamin C, or to the combination. It also is not known whether it will occur in other patient populations.
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Acidification of the urine by vitamin C might increase salsalate levels.
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It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels (3046). However, short-term use of up to 6 grams/day vitamin C does not seem to affect urinary pH or salicylate excretion (10588,10589), suggesting this interaction probably is not clinically significant.
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High-dose vitamin C might reduce the levels and effectiveness of warfarin.
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Vitamin C in high doses may cause diarrhea and possibly reduce warfarin absorption (11566). There are reports of two people who took up to 16 grams daily of vitamin C and had a reduction in prothrombin time (9804,9806). Lower doses of 5-10 grams daily can also reduce warfarin absorption. In many cases, this does not seem to be clinically significant (9805,9806,11566,11567). However, a case of warfarin resistance has been reported for a patient who took vitamin C 500 mg twice daily. Cessation of vitamin C supplementation resulted in a rapid increase in international normalized ratio (INR) (90942). Tell patients taking warfarin to avoid taking vitamin C in excessively high doses (greater than 10 grams daily). Lower doses may be safe, but the anticoagulation activity of warfarin should be monitored. Patients who are stabilized on warfarin while taking vitamin C should avoid adjusting vitamin C dosage to prevent the possibility of warfarin resistance.
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Below is general information about the adverse effects of the known ingredients contained in the product C4 Ripped Icy Blue Razz. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
General ...Orally, topically, and intravenously, alpha-ketoglutarate seems to be well tolerated.
General
...Orally, beta-alanine seems to be generally well tolerated.
Most Common Adverse Effects:
Orally: Flushing, paresthesia.
Gastrointestinal ...While rare, digestion problems have been reported with oral beta-alanine use (94341).
Neurologic/CNS ...Orally, beta-alanine can cause a dose-dependent feeling of pins and needles (paresthesias) along with skin flushing (16438,94333,94335,94338,94341,94342,94349,101028,101029,106711). This generally starts on the scalp within 20 minutes of the dose, spreading to most of the body, and lasting for about an hour. This was described as severe at a dose of 40 mg/kg, tolerable at a dose of 20 mg/kg, and very mild at a dose of 10 mg/kg. At the lowest dose it only occurred in 25% of subjects (16438). In some studies, beta-alanine has been given as frequently as 8 times per day so that each dose can be kept below 10 mg/kg (16438,16439). Other clinical research shows that taking beta-alanine in a tablet formulation eliminates the presence of parasthesias at a dose of 1.6 grams when compared with a solution made from powdered beta-alanine. This effect may be due to delayed absorption (97974,97975). Although paresthesias still occur with sustained-release formulations, their presence is less frequent when compared with immediate-release formulations (101029).
General
...Caffeine in moderate doses is typically well tolerated.
Most Common Adverse Effects:
Orally: Anxiety, dependence with chronic use, diarrhea, diuresis, gastric irritation, headache, insomnia, muscular tremors, nausea, and restlessness.
Serious Adverse Effects (Rare):
Orally: Stroke has been reported rarely.
Cardiovascular
...Caffeine can temporarily increase blood pressure.
Usually, blood pressure increases 30 minutes after ingestion, peaks in 1-2 hours, and remains elevated for over 4 hours (36539,37732,37989,38000,38300).
Although acute administration of caffeine can cause increased blood pressure, regular consumption does not seem to increase either blood pressure or pulse, even in mildly hypertensive patients (1451,1452,2722,38335). However, the form of caffeine may play a role in blood pressure increase after a more sustained caffeine use. In a pooled analysis of clinical trials, coffee intake was not associated with an increase in blood pressure, while ingesting caffeine 410 mg daily for at least 7 days modestly increased blood pressure by an average of 4.16/2.41 mmHg (37657). Another meta-analysis of clinical research shows that taking caffeine increases systolic and diastolic blood pressure by approximately 2 mmHg when compared with control. Preliminary subgroup analyses suggest that caffeine may increase blood pressure more in males or at doses over 400 mg (112738).
When used prior to intensive exercise, caffeine can increase systolic blood pressure by 7-8 mmHg (38308). The blood pressure-raising effects of caffeine are greater during stress (36479,38334) and after caffeine-abstinence of at least 24 hours (38241).
Epidemiological research suggests there is no association of caffeine consumption with incidence of hypertension (38190). Habitual coffee consumption also doesn't seem to be related to hypertension, but habitual consumption of sugared or diet cola is associated with development of hypertension (13739).
Epidemiological research has found that regular caffeine intake of up to 400 mg daily is not associated with increased incidence of atrial fibrillation (38018,38076,91028,91034,97451,97453,103708), atherosclerosis (38033), cardiac ectopy (91127), stroke (37804), ventricular arrhythmia (95948,97453), and cardiovascular disease in general (37805,98806). One clinical trial shows that in adults with diagnosed heart failure, consumption of 500 mg of coffee does not result in an increased risk for arrhythmia during exercise (95950). However, caffeine intake may pose a greater cardiovascular risk to subjects that are not regular users of caffeine. For example, in one population study, caffeinated coffee consumption was associated with an increased risk of ischemic stroke in subjects that don't regularly drink coffee (38102). In a population study in Japanese subjects, caffeine-containing medication use was modestly associated with hemorrhagic stroke in adults that do not consume caffeine regularly (91059).
The most common side effect of caffeine in neonates receiving caffeine for apnea is tachycardia (98807,114658).
Dermatologic ...There are several case reports of urticaria after caffeine ingestion (36546,36448,36475).
Endocrine
...Some evidence shows caffeine is associated with fibrocystic breast disease or breast cancer in females; however, this is controversial since findings are conflicting (8043,108806).
Restricting caffeine in females with fibrocystic breast conditions doesn't seem to affect breast nodularity, swelling, or pain (8996). A population analysis of the Women's Health Initiative observational study has found no association between consumption of caffeine-containing beverages and the incidence of invasive breast cancer in models adjusted for demographic, lifestyle, and reproductive factors (108806). Also, a dose-response analysis of 2 low-quality observational studies has found that high consumption of caffeine is not associated with an increased risk of breast cancer (108807).
Clinical research in healthy adults shows that an increase consumption of caffeine results in increased insulin resistance (91023).
Gastrointestinal ...Gastrointestinal upset, nausea, diarrhea, abdominal pain, and fecal incontinence may occur with caffeine intake (36466,37755,37806,37789,37830,38138,38136,38223,95956,95963). Also, caffeine may cause feeding intolerance and gastrointestinal irritation in infants (6023). Perioperative caffeine during cardiopulmonary bypass surgery seems to increase the rate of postoperative nausea and vomiting (97451). Caffeine and coffee consumption have been associated with an increase in the incidence of heartburn (37545,37575,38251,38259,38267) and gastrointestinal esophageal reflux disease (GERD) (38329,37633,37631,37603).
Genitourinary ...Caffeine, a known diuretic, may increase voiding, give a sense of urgency, and irritate the bladder (37874,37961,104580). In men with lower urinary tract symptoms, caffeine intake increased the risk of interstitial cystitis/painful bladder syndrome (38115). Excessive caffeine consumption may worsen premenstrual syndrome. Consumption of up to 10 cups of caffeinated drinks daily was associated with increased severity of premenstrual syndrome (38177). Finally, population research shows that exposure to caffeine was not associated with an increased risk of endometriosis (91035).
Immunologic ...Caffeine can cause anaphylaxis in sensitive individuals, although true IgE-mediated caffeine allergy seems to be relatively rare (11315).
Musculoskeletal
...Caffeine can induce or exacerbate muscular tremors (38136,37673,38161).
There has also been a report of severe rhabdomyolysis in a healthy 40-year-old patient who consumed an energy drink containing 400 mg of caffeine (4 mg/kg) and then participated in strenuous weightlifting exercise (108818).
Epidemiological evidence regarding the relationship between caffeine use and the risk for osteoporosis is contradictory. Caffeine can release calcium from storage sites and increase its urinary excretion (2669,10202,11317,111489). Females with a genetic variant of the vitamin D receptor appear to be at an increased risk for the detrimental effect of caffeine on bone mass (2669). However, moderate caffeine intake, less than 300 mg daily, does not seem to significantly increase osteoporosis risk in most postmenopausal adults with normal calcium intake (2669,6025,10202,11317). Premature infants treated with intravenous caffeine for apnea of prematurity, have a lower bone mineral content compared with infants who are not treated with caffeine, especially when treatment extends beyond 14 days (111489).
Neurologic/CNS ...Caffeine can cause headaches, anxiety, jitteriness, restlessness, and nervousness (36466,37694,37755,37806,37865,37830,37889,38223,95952). In adolescents, there is an inverse correlation between the consumption of caffeine and various measurements of cognitive function (104579). Insomnia is a frequent adverse effect in children (10755). Caffeine may result in insomnia and sleep disturbances in adults as well (36445,36483,36512,36531,37598,37795,37819,37862,37864,37890)(37968,37971,38091,38242,91022,92952). Additionally, caffeine may exacerbate sleep disturbances in patients with acquired immunodeficiency syndrome (AIDS) (10204). Combining ephedra with caffeine can increase the risk of adverse effects. Jitteriness, hypertension, seizures, temporary loss of consciousness, and hospitalization requiring life support has been associated with the combined use of ephedra and caffeine (2729). Finally, epidemiological research suggests that consuming more than 190 mg of caffeine daily is associated with an earlier onset of Huntington disease by 3.6 years (91078).
Ocular/Otic
...In individuals with glaucoma, coffee consumption and caffeine intake has been found to increase intraocular pressure (8540,36464,36465,37670).
The magnitude of this effect seems to depend on individual tolerance to caffeine. Some research in healthy young adults shows that caffeine increases intraocular pressure to a greater degree in low-consumers of caffeine (i.e., 1 cup of coffee or less daily) when compared to high-consumers (i.e., those consuming 2 cups of coffee or more daily) (100371). The peak increase of intraocular pressure seems to occur at about 1.5 hours after caffeine ingestion, and there is no notable effect 4 hours after ingestion (36462,100371).
Oncologic ...Most human studies which have examined caffeine or methylxanthine intake have found that they do not play a role in the development of various cancers, including breast, ovarian, brain, colon, rectal, or bladder cancer (37641,37737,37775,37900,38050,38169,38220,91054,91076,108806).
Psychiatric
...Caffeine may lead to habituation and physical dependence (36355,36453,36512,36599), with amounts as low as 100 mg daily (36355,36453).
An estimated 9% to 30% of caffeine consumers could be considered addicted to caffeine (36355). Higher doses of caffeine have caused nervousness, agitation, anxiety, irritability, delirium, depression, sleep disturbances, impaired attention, manic behavior, psychosis and panic attacks (36505,37717,37818,37839,37857,37982,38004,38017,38028,38072)(38079,38138,38306,38325,38331,38332,97464). Similar symptoms have been reported in a caffeine-naïve individual experiencing fatigue and dehydration after a dose of only 200 mg, with resolution of symptoms occurring within 2 hours (95952).
Withdrawal: The existence or clinical importance of caffeine withdrawal is controversial. Some researchers think that if it exists, it appears to be of little clinical significance (11839). Headache is the most common symptom, due to cerebral vasodilation and increased blood flow (37769,37991,37998). Other researchers suggest symptoms such as tiredness and fatigue, decreased energy, alertness and attentiveness, drowsiness, decreased contentedness, depressed mood, difficulty concentration, irritability, and lack of clear-headedness are typical of caffeine withdrawal (13738). Withdrawal symptoms typically occur 12-24 hours after the last dose of caffeine and peak around 48 hours (37769,36600). Symptoms may persist for 2-9 days. Withdrawal symptoms such as delirium, nausea, vomiting, rhinorrhea, nervousness, restlessness, anxiety, muscle tension, muscle pains, and flushed face have been described. However, these symptoms may be from nonpharmacological factors related to knowledge and expectation of effects. Clinically significant symptoms caused by caffeine withdrawal may be uncommon (2723,11839). In a case report, caffeine consumption of 560 mg daily was associated with increased suicidality (91082).
Renal ...Data on the relationship between caffeine intake and kidney stones are conflicting. Some clinical research shows that caffeine consumption may increase the risk of stone formation (37634,111498), while other research shows a reduced risk with increasing caffeine intakes (111498). A meta-analysis of 7 studies found that overall, there is an inverse relationship, with a 32% decrease in the risk of kidney stones between the lowest and highest daily intakes of caffeine (111498).
Other ...People with voice disorders, singers, and other voice professionals are often advised against the use of caffeine; however, this recommendation has been based on anecdotal evidence. One small exploratory study suggests that caffeine ingestion may adversely affect subjective voice quality, although there appears to be significant intra-individual variability. Further study is necessary to confirm these preliminary findings (2724).
General
...Orally and intravenously, calcium is well-tolerated when used appropriately.
Most Common Adverse Effects:
Orally: Belching, constipation, diarrhea, flatulence, and stomach upset.
Serious Adverse Effects (Rare):
Orally: Case reports have raised concerns about calciphylaxis and kidney stones.
Cardiovascular
...There has been concern that calcium intake may be associated with an increased risk of cardiovascular disease (CVD) and coronary heart disease (CHD), including myocardial infarction (MI).
Some clinical research suggests that calcium intake, often in amounts over the recommended daily intake level of 1000-1300 mg daily for adults, is associated with an increased risk of CVD, CHD, and MI (16118,17482,91350,107233). However, these results, particularly meta-analyses, have been criticized for excluding trials in which calcium was administered with vitamin D (94137). Many of these trials also only included postmenopausal females. Other analyses report conflicting results, and have not shown that calcium intake affects the risk of CVD, CHD, or MI (92994,93533,97308,107231). Reasons for these discrepancies are not entirely clear. It may relate to whether calcium is taken as monotherapy or in combination with vitamin D. When taken with vitamin D, which is commonly recommended, calcium supplementation does not appear to be associated with an increased risk of CVD, CHD, or MI (93533,107231). Also, the association between calcium supplementation and CVD, CHD, or MI risk may be influenced by the amount of calcium consumed as part of the diet. Supplementation with calcium may be associated with an increased risk of MI in people with dietary calcium intake above 805 mg daily, but not in those with dietary calcium intake below 805 mg daily (17482). To minimize the possible risk of CVD, CHD, or MI, advise patients not to consume more than the recommended daily intake of 1000-1200 mg and to consider total calcium intake from both dietary and supplemental sources (17484). While dietary intake of calcium is preferred over supplemental intake, advise patients who require calcium supplements to take calcium along with vitamin D, as this combination does not appear to be associated with an increased risk of MI (93533).
Rarely, calcium intake can increase the risk of calciphylaxis, which usually occurs in patients with kidney failure. Calciphylaxis is the deposition of calcium phosphate in arterioles, which causes skin ulcers and skin necrosis. In a case report, a 64-year-old female with a history of neck fracture, sepsis, and ischemic colitis presented with painful leg ulcers due to calciphylaxis. She discontinued calcium and vitamin D supplementation and was treated with sodium thiosulfate and supportive care (95816).
Gastrointestinal ...Orally, calcium can cause belching, flatulence, nausea, gastrointestinal discomfort, and diarrhea (1824,1843,12950,38803). Although constipation is frequently cited as an adverse effect of calcium, there is no scientific substantiation of this side effect (1824,1843,1844,1845,12950,38978). Calcium carbonate has been reported to cause acid rebound, but this is controversial (12935,12936).
Oncologic ...There is some concern that very high doses of calcium might increase the risk of prostate cancer. Some epidemiological evidence suggests that consuming over 2000 mg/day of dietary calcium might increase the risk for prostate cancer (4825,12949). Additional research suggests that calcium intake over 1500 mg/day might increase the risk of advanced prostate cancer and prostate cancer mortality (14132). Consumption of dairy products has also been weakly linked to a small increase in prostate cancer risk (98894). However, contradictory research suggests no association between dietary intake of calcium and overall prostate cancer risk (14131,14132,104630). More evidence is needed to determine the effect of calcium, if any, on prostate cancer risk.
Renal ...Kidney stones have been reported in individuals taking calcium carbonate 1500 mg daily in combination with vitamin D 2000 IU daily for 4 years (93943).
General
...Orally, capsicum is generally well tolerated in amounts typically found in food or when the extract is used in doses of up to 200 mg daily.
Topically and intranasally, capsaicin, a constituent of capsicum, is generally well tolerated.
Most Common Adverse Effects:
Orally: Belching, bloating, burning, diarrhea, dyspepsia, gas, headache, mild constipation, nausea, rhinorrhea, skin flushing, and sweating.
Serious Adverse Effects (Rare):
Orally: Cases of myocardial infarction and hypertensive crisis have been reported.
Cardiovascular
...Orally, palpitation was reported in one clinical trial (105196).
One case of myocardial infarction has been reported in a 41-year-old male without cardiovascular risk factors; the event was attributed to the use of an oral capsicum pepper pill that the patient had been taking for weight loss (40768). Another case of coronary vasospasm and acute myocardial infarction has been reported for a healthy 29-year-old male; the event was attributed to the use of a topical capsicum-containing patch that the patient had been applying to the middle of the back for 6 days (40658). Two cases of arterial hypertensive crisis have been reported for individuals who ingested a large amount of peppers and chili peppers the day before. One of the patients also had an acute myocardial infarction, and the other had high levels of thyroid stimulating hormone (40569,40606).
Dermatologic
...Orally, capsicum or its constituent capsaicin may cause urticaria and skin wheals in rare cases (96457,105203).
Topically, capsicum can cause a prickling sensation, itching, pain, burning, edema, stinging, irritation, rash, and erythema. About 1 in 10 patients who use capsaicin topically discontinue treatment because of adverse effects. These effects seem to occur more often with topical formulations containing higher concentrations of capsaicin, the active constituent of capsicum. Side effects tend to diminish with continued use (12401,15260,15261,40358,40439,40483,40547,40676,40682,40719)(40784,40847,92979,92983,92984,96453,105193,105197,105202,111514). In one case, application of a capsaicin 8% patch (Qutenza) for 60 minutes caused a second-degree burn, characterized by burning, erythema, severe pain, and blistering at the administration site. The burn was treated with topical corticosteroids, but 9 months later neuropathic pain persisted, resulting in limited mobility. It is unclear whether the mobility sequalae were caused by topical capsaicin or the patient's pre-existing neurological disorders (111514). Skin contact with fresh capsicum fruit can also cause irritation or contact dermatitis (12408).
Intranasally, capsaicin can cause nasal burning and pain in most patients. It also often causes lacrimation, sneezing, and excessive nasal secretion; however, these side effects appear to diminish with repeat applications (14323,14329,14358). In some cases, the burning sensation disappears after 5-8 applications (14351,14358). In some cases, patients are pretreated with intranasal lidocaine to decrease the pain of intranasal capsaicin treatment. However, even with lidocaine pretreatment, patients seem to experience significant pain (14324).
Gastrointestinal
...Orally, capsicum can cause upper abdominal discomfort, including irritation, fullness, dyspepsia, gas, bloating, nausea, epigastric pain and burning, anal burning, diarrhea, mild constipation, and belching (12403,12410,40338,40427,40456,40503,40560,40584,40605,40665)(40718,40725,40745,40808,40828,96456,96457,105194,105196).
There is a case report of a 3-year-old female who experienced a burning and swollen mouth and lips after touching the arm of a parent that had been treated with a capsaicin patch and then placing the fingers in the mouth (105199). Excessive amounts of capsaicin can lead to gastroenteritis and hepatic necrosis (12404). In a case report, a 40-year-old male with diabetes consumed white wine daily and chewed cayenne which was thought to result in black teeth stains and loss of enamel (40809). Some preliminary research links ingestion of capsaicin with stomach and gallbladder cancer; however the link may be due to contamination of capsaicin products with carcinogens (40771).
Topically, capsaicin can cause diarrhea and vomiting (105202).
Immunologic ...In a case report, a 34-year-old female had anaphylaxis involving difficulty breathing and stupor and also urticaria after consuming a red bell pepper, which is in the capsicum genus. The causal chemical was theorized to be 1,3-beta-glucanase (92978). In another case report, a 33-year-old female experienced angioedema, difficulty breathing and swallowing, and urticaria after ingesting raw green and red peppers (92982).
Neurologic/CNS ...Orally, capsicum can cause sweating and flushing of the head and neck, lacrimation, headache, faintness, and rhinorrhea (7005,12410,105196,105203). Topically, applying capsaicin can cause headache (96450,105202). Injection of capsaicin into the intermetatarsal space has also been associated with headache (96454).
Ocular/Otic
...Topically, capsicum can be extremely irritating to the eyes and mucous membranes.
Capsicum oleoresin, an oily extract in pepper self-defense sprays, causes intense eye pain. It can also cause erythema, blepharospasm, tearing, shortness of breath, and blurred vision. In rare cases, corneal abrasions have occurred (12408,12409,40345,40348,40383,40720,40857).
Inhalation of capsicum can cause eye irritation, and allergic alveolitis (5885). In a case report, a 38-year-old female had acute anterior uveitis that developed about 12 hours after using a specific patch (Isola Capsicum N Plus) that contained capsaicin 1.5 mg per patch and methyl salicylate 132 mg per patch for neck pain. The uveitis was controlled with topical steroids and did not recur (92977).
Oncologic ...Population research suggests that moderate to high intake of capsaicin, the active constituent of capsicum, is associated with an increased risk of gastric cancer, while low intake is associated with a decreased risk. It is not clear from the study what amount of capsaicin is considered high versus low intake (92988). Additionally, some research suggests that any link may be due to contamination of capsaicin products with carcinogens (40771).
Pulmonary/Respiratory
...Orally, difficulty breathing was reported in a clinical trial (105196).
Topically, nasopharyngitis related to the use of a cream containing capsaicin has been reported (105202).
Inhalation of capsicum and exposure to capsicum oleoresin spray can cause cough, dyspnea, pain in the nasal passages, sneezing, rhinitis, and nasal congestion (5885,15016,40522,40546,40647). In rare cases, inhalation of the capsicum oleoresin or pepper spray has caused cyanosis, apnea, respiratory arrest and death in people. Death was caused by asphyxiation probably due to acute laryngeal edema and bronchoconstriction from inhalation of the capsicum oleoresin spray (40546,40672,40837,40879).
In a case report, a 47-year-old female who was exposed to capsaicin gas for more than 20 minutes experienced acute cough, shortness of breath, short-term chest pain, wheezing, and difficulty breathing for months afterwards (92980). In rare cases, exposure to capsicum oleoresin spray resulted in apnea, pulmonary injury, cyanosis, and even respiratory arrest (40383,40546).
General
...Orally, intravenously, ophthalmologically, and by inhalation, coleus seems to be well tolerated.
Most Common Adverse Effects:
Orally: Constipation, diarrhea, nausea, vomiting.
Intravenously: Flushing, hypotension, tachycardia.
Ophthalmologically: Conjunctival hyperemia, stinging eyes.
Inhalation: Irritation of the respiratory tract, restlessness, tremor.
Cardiovascular ...Intravenously, the coleus constituent, forskolin, can cause tachycardia, flushing and hypotension (7279,44424,44431).
Dermatologic ...Two cases of contact dermatitis have been reported following airborne exposure to coleus (44426,44418).
Gastrointestinal ...Orally, coleus can cause dose-related diarrhea and other gastrointestinal symptoms. Increased bowel movements and loose stools have been reported in 1 of 15 patients taking coleus extract in a clinical trial (91885). Some retrospective evidence reports about a 10% rate of gastrointestinal adverse effects from oral coleus use; 81% of these adverse effects were related to diarrhea. Other reported adverse effects which occurred at a much lower rate, include nausea, vomiting, and/or constipation. Gastrointestinal effects appear to be dose-related; those taking less than 250 mg of coleus extract did not report any diarrhea, while all patients taking 1000 mg of coleus extract reported diarrhea (100851).
Neurologic/CNS ...Inhalation of forskolin, a constituent of coleus, can cause tremor and restlessness (7281).
Ocular/Otic ...Ophthalmologically, forskolin, a constituent of coleus, can cause stinging of the eyes and conjunctival hyperemia (7283).
Pulmonary/Respiratory ...Inhalation of forskolin, a constituent of coleus, can cause throat and upper respiratory tract irritation, and mild to moderate cough (7281).
General
...Orally, adverse effects to cowhage seem to be rare; however, a thorough safety evaluation has not been conducted.
Topically, cowhage bean pod or seed may be unsafe.
Most Common Adverse Effects:
Orally: Diarrhea, flatulence, mucosal irritation.
Topically: Erythema, pruritus, rash.
Cardiovascular ...Orally, cowhage has been reported to cause palpitations (7021,7203)
Dermatologic
...Orally, ingestion of hairs from the bean pod or seed can result in significant mucosal irritation and should be avoided.
Topically, hairs on cowhage bean pod or seed can cause severe pruritus (6898). Symptoms include severe itching, burning, inflammation, and erythematous macular rashes (18,6898). Symptoms resolve spontaneously within several hours, but may also be relieved with antihistamines (6898). The hairs can be removed from the skin by washing, but the hairs can also be retained, and transferred to other people, in fabrics and carpets. Clothing and other materials that come in contact with cowhage hairs should also be thoroughly washed (6898).
Gastrointestinal ...Orally, cowhage has been reported to cause flatulence, diarrhea, and dry mouth (7021,7203). Orally, a specific powdered cowhage seed extract (Zandopa, formerly HP-200; Zandu Pharmaceuticals) has been reported to cause nausea, abdominal distention, and vomiting in clinical research when taken in amounts of 22.5-67.5 grams divided into 2-5 doses per day (7020).
Musculoskeletal ...Orally, dyskinesia has been reported in clinical research in about 3% of patients taking a specific powdered cowhage seed extract (Zandopa, formerly HP-200; Zandu Pharmaceuticals) 22. 5-67.5 grams divided into 2-5 doses daily (7020).
Neurologic/CNS ...Orally, cowhage has been reported to cause headaches (7021,7203). Orally, insomnia has been reported in clinical research in about 3% of patients taking a specific powdered cowhage seed extract (Zandopa, formerly HP-200; Zandu Pharmaceuticals) 22.5 grams to 67.5 grams divided into 2-5 doses daily (7020).
Psychiatric ...In a case report, cowhage caused an outbreak of acute toxic psychosis. Symptoms of psychosis included confusion, giddiness, agitation, hallucinations, and paranoid delusions. The cowhage-induced psychosis was successfully treated with intravenous chlorpromazine (7021).
Other ...Orally, cowhage has been reported to cause sweating and changes in urine color, (7021,7203). Theoretically, due to the levodopa constituent, cowhage is likely to cause the same adverse effects that have been attributed to purified, prescription levodopa. Some of these side effects include elevated liver enzymes, respiratory disturbances, urinary retention, muscle cramps, and priapism (15). However, these effects have not yet been reported for cowhage.
General
...Orally, folic acid is generally well-tolerated in amounts found in fortified foods, as well as in supplemental doses of less than 1 mg daily.
Most Common Adverse Effects:
Orally: At doses of 5 mg daily - abdominal cramps, diarrhea, and rash. At doses of 15 mg daily - bitter taste, confusion, hyperactivity, impaired judgment, irritability, nausea, sleep disturbances.
Serious Adverse Effects (Rare):
Orally: Cancer (long-term use), cardiovascular complications, liver injury, seizures.
All ROAs: Allergic reactions such as bronchospasm and anaphylactic shock.
Cardiovascular ...There is some concern that high oral doses of folic acid might increase the risk of adverse cardiovascular outcomes. Clinical research shows that taking doses of 800 mcg to 1.2 mg/day might increase the risk of adverse cardiovascular events in patients with cardiovascular disease (12150,13482). High doses of folic acid might promote cell growth by providing large amounts of the biochemical precursors needed for cell replication. Overgrowth of cells in the vascular wall might increase the risk of occlusion (12150). Although some research suggests that use of folic acid might increase the need for coronary revascularization, analysis of multiple studies suggests that taking folic acid up to 5 mg/day for up to 24 months does not appear to affect coronary revascularization risk (90798).
Dermatologic ...Orally, folic acid 1-5 mg daily can cause rash (7225,90375,91319). Folic acid 15 mg daily can sometimes cause allergic skin reactions (15).
Gastrointestinal ...Orally, folic acid 5 mg daily can cause abdominal cramps and diarrhea (7225). Folic acid 15 mg daily can sometimes cause nausea, abdominal distention, flatulence, and bitter taste in the mouth (15). In children aged 6-30 months at risk of malnourishment, taking a nutritional supplement (Nutriset Ltd) enriched in folic acid 75-150 mcg daily, with or without vitamin B 12 0.9-1.8 mcg daily, for 6 months increases the likelihood of having persistent diarrhea (90391).
Hepatic ...Liver dysfunction, with jaundice and very high liver enzymes, occurred in a 30-year-old pregnant patient with severe nausea and vomiting taking a folic acid supplement (Folic acid, Nature Made) 400 mcg daily. Based on the timing of ingestion, the lack of other etiological factors, a positive drug-induced lymphocyte stimulation test, and liver function normalization once the folic acid had been stopped, the authors suggest the folic acid supplement was the cause. However, the authors did not determine which substance in the folic acid supplement was responsible and therefore it cannot be determined that folic acid itself was the cause (91309).
Neurologic/CNS ...Orally, folic acid 15 mg daily can sometimes cause altered sleep patterns, vivid dreaming, irritability, excitability, hyperactivity, confusion, and impaired judgment (15). Large doses of folic acid can also precipitate or exacerbate neuropathy in people deficient in vitamin B12 (6243). Use of folic acid for undiagnosed anemia has masked the symptoms of pernicious anemia, resulting in lack of treatment and eventual neurological damage (15). Patients should be warned not to self-treat suspected anemia. There is also some concern that consuming high amounts of folic acid from the diet and/or supplements might worsen cognitive decline in older people. A large-scale study suggests that people over 65 years of age, who consume large amounts of folic acid (median of 742 mcg/day), have cognitive decline at a rate twice as fast as those consuming smaller amounts (median of 186 mcg/day). It's not known if this is directly attributable to folic acid. It is theorized that it could be due to folic acid masking a vitamin B12 deficiency. Vitamin B12 deficiency is associated with cognitive decline (13068). More evidence is needed to determine the significance of this finding. For now, suggest that most patients aim for the recommended folic acid intake of 400 mcg/day.
Oncologic
...There is some concern that high dose folic acid might increase the risk of cancer, although research is unclear and conflicting.
A large-scale population study suggests that taking a multivitamin more than 7 times per week with a separate folic acid supplement significantly increased the risk of prostate cancer (15607). Clinical research also shows that taking folic acid 1 mg daily increase the absolute risk of prostate cancer by 6.4% over a 10-year period when compared with placebo. However, those with a higher baseline dietary intake of folic acid had a lower rate of prostate cancer, but this was not statistically significant. Also, folate and folic acid intake in patients with prostate cancer is not associated with the risk of prostate cancer recurrence after radical prostatectomy (91317). However, it is possible that discrepancies are due to dietary folate versus folic acid intake. Large analyses of population studies suggest that while dietary folate/folic acid is not associated with prostate cancer, high blood folate/folic acid increases the risk of prostate cancer (50411,91316).
Additional clinical research shows that taking folic acid 800 mcg daily, in combination with vitamin B12 400 mcg, significantly increases the risk of developing cancer, especially lung cancer, and all-cause mortality in patients with cardiovascular disease (17041). However, this may be due to vitamin B12, as other observational research found that higher vitamin B12 levels are linked with an increased risk for lung cancer (102383). Meta-analyses of large supplementation trials of folic acid at levels between 0.5-2.5 mg daily also suggest an increased risk of cancer (50497,110318). Also, in elderly individuals, taking folic acid 400 mcg daily with vitamin B12 500 mcg daily increased the risk of cancer. The risk was highest in individuals over 80 years of age and in females and mainly involved gastrointestinal and colorectal cancers (90393).
Not all researchers suspect that high intake of folic acid supplements might be harmful. Some research suggests that increased dietary intake of folic acid, along with other nutrients, might be protective against cancer (16822). A meta-analysis of multiple clinical trials suggests that folic acid supplementation studies with folic acid levels between 500 mcg to 50 mg/day does not increase the risk of general or site-specific cancer for up to 7 years (91312,91321). Also, a post-hoc subgroup analysis of results from clinical research in adults with a history of recent stroke or ischemic attack suggests that taking folic acid, vitamin B12, and vitamin B6 does not increase cancer risk overall, although it was associated with an increased risk of cancer in patients who also had diabetes (90378).
Psychiatric ...Orally, folic acid 15 mg daily can sometimes cause exacerbation of seizure frequency and psychotic behavior (15).
Pulmonary/Respiratory ...Folic acid use in late pregnancy has been associated with an increased risk of persistent and childhood asthma at 3. 5 years in population research (50380). When taken pre-pregnancy or early in pregnancy, population research has not found an association with increased risk of asthma or allergies in childhood (90799,103979). Folic acid use in pregnancy has been associated with a slightly increased risk of wheeze and lower respiratory tract infections up to 18 months of age in population research (50328).
General ...Orally, green coffee appears to be well-tolerated. Although green coffee contains caffeine, it is present in small quantities which are less likely to cause adverse effects. Green coffee contains about 20-50 mg caffeine per cup, compared with about 100 mg caffeine per cup of brewed coffee.
Cardiovascular
...Although acute administration of caffeine, a constituent of green coffee, can cause increased blood pressure, regular consumption does not seem to increase either blood pressure or pulse, even in mildly hypertensive patients (1451,1452,2722,13739).
Drinking one or more cups daily of caffeinated coffee, such as green coffee, also doesn't seem to increase the risk of developing hypertension in habitual coffee drinkers (8033,13739).
Chlorogenic acids found in green coffee extracts may adversely affect plasma homocysteine levels. In one randomized controlled trial, 2 grams of chlorogenic acids (the amount found in about 1.5 L of strong coffee) daily for one week resulted in a 12% increase in plasma homocysteine levels (8035). However, in another trial of green coffee extract in a dose equivalent to 140 mg of chlorogenic acids daily for 4 months, there was a slight decrease in plasma homocysteine levels from baseline, but this did not differ significantly from placebo treatment (17970).
The diterpenes cafestol and kahweol found in green coffee beans have been implicated in the hypercholesterolemic effects of unfiltered coffee (19336,53599). However, these compounds are removed from some green coffee extracts. For instance, Svetol (Naturex, South Hackensack, NJ) is reported to contain less than 4 ppm of cafestol and kahweol (88171).
Dermatologic ...Positive skin tests and symptoms of contact allergy have been reported in workers exposed to green coffee bean dust (53568,53653).
Endocrine
...Some evidence shows that caffeine, a constituent of green coffee, is associated with fibrocystic breast disease, breast cancer, and endometriosis in females; however, this is controversial since findings are conflicting (8043).
Restricting caffeine in females with fibrocystic breast conditions doesn't seem to affect breast nodularity, swelling, or pain (8996). A population analysis of the Women's Health Initiative observational study has found no association between consumption of caffeine-containing beverages and the incidence of invasive breast cancer in models adjusted for demographic, lifestyle, and reproductive factors (108806). Also, a dose-response analysis of 2 low-quality observational studies has found that high consumption of caffeine is not associated with an increased risk of breast cancer (108807).
Clinical research in healthy adults shows that increased consumption of caffeine results in increased insulin resistance (91023).
Gastrointestinal ...Orally, stomach irritation was reported by one person in a clinical trial of green coffee extract (104831).
Musculoskeletal ...Epidemiological evidence regarding the relationship between caffeine, which is found in green coffee, and the risk of osteoporosis is contradictory. Caffeine can increase urinary excretion of calcium (2669,10202,11317). Females identified with a genetic variant of the vitamin D receptor appear to be at an increased risk of the detrimental effect of caffeine on bone mass (2669). However, moderate caffeine intake, less than 300 mg per day, does not seem to significantly increase osteoporosis risk in most postmenopausal adults with normal calcium intake (2669,6025,10202,11317).
Neurologic/CNS ...Orally, dizziness was reported by one person in a clinical trial of green coffee extract (104831).
Ocular/Otic ...Conjunctivitis caused by green coffee bean dust in coffee workers has been described in case reports (53657,53589).
Psychiatric ...Chronic use of caffeine, especially in large amounts, may produce tolerance, habituation, and psychological dependence (3719). Abrupt discontinuation of caffeine may result in physical withdrawal symptoms, including headache, fatigue, drowsiness, decreased physical energy, difficulty concentrating, depression, anxiety, irritability, and reduced alertness (13738). Certain populations such as children and the elderly may be more susceptible to the adverse effects of caffeine (13736).
Pulmonary/Respiratory ...Occupational exposure to green coffee beans has been documented to cause numerous adverse respiratory reactions, including bronchial reactivity, asthma, and rhinitis (53589,53641,53644,53648,53650,53665). Healthy subjects exposed experimentally to green coffee dust displayed acute decreases in expiratory flow rates (53653). In one study, green coffee workers displayed numerous acute respiratory symptoms when exposed to dust; these included coughing, increased sputum, sneezing, difficulty in breathing, running nose, and wheezing; these symptoms resolved after leaving work (53647).
General
...Orally and intravenously, L-carnitine is generally well tolerated.
Most Common Adverse Effects:
All routes of administration: Abdominal cramps, abdominal pain, diarrhea, gastritis, heartburn, nausea, reduced appetite, and vomiting. A fish-like body odor has also been reported.
Serious Adverse Effects (Rare):
All routes of administration: Seizures.
Cardiovascular ...According to population research, plasma L-carnitine levels are associated with increased risk of cardiovascular disease and major cardiac events (90635). However, oral supplementation with L-carnitine does not appear to be associated with an increased risk of cardiovascular disease. In fact, a meta-analysis of clinical research shows that L-carnitine supplementation is associated with a reduction in all-cause mortality, as well as ventricular arrhythmias and the development of angina and does not increase the development of heart failure or myocardial reinfarction (59037). Also, another meta-analysis suggests that L-carnitine does not affect mortality or cardiovascular outcomes in patients with a previous myocardial infarction (90630).
Dermatologic ...Orally, L-carnitine has been reported to cause skin rash in a small number of cases (16105,91724). Two patients in a hair growth study using topical carnitine reported mild itching and increased dandruff, while a third reported strong itching with reddish bumps and a burning sensation (58390). When a specific formulation containing L-carnitine, licochalcone, and 1,2-decanediol was applied to the face, mild skin dryness and tightness was reported by 12% of volunteers, compared with 4% to 8% of those in the vehicle-only control group (26493).
Gastrointestinal ...Orally and intravenously, L-carnitine has been associated with nausea, epigastric discomfort, vomiting, abdominal cramps, heartburn, gastritis, anorexia, and diarrhea (3616,3624,59030,95069,95070,101562,107410,111870,111887,111891). Orally, diarrhea or colitis symptoms (1433,3630,16105,16107,16111,23437,58523,58554,59020,90623), nausea and abdominal pain (16105,16106,26499,58169,58392,58554,90623,90634), indigestion (26703), and constipation (58523) have been reported in various clinical trials.
Hematologic ...In one case report, L-carnitine 990 mg twice daily was started in a female presenting to hospital with valproic acid toxicity. Blood phosphorous levels subsequently fell from 2.3 mg/dL to 1.3 mg/dL over 4 days. After discontinuation of L-carnitine, blood phosphorus levels increased to 1.8 mg/dL. The authors suggested that the role of L-carnitine in improved protein metabolism may play a role in the declining levels of phosphorous in the blood and increased risk of hypophosphatemia (90628).
Neurologic/CNS ...Orally or intravenously, L-carnitine has been associated with seizures (3616). Orally, use of L-carnitine in clinical trials has resulted in headache, although this event is rare (58554,95070,111891). L-carnitine may also cause agitation (95070).
Other ...Orally or intravenously, L-carnitine has been associated with a fish-like body odor (1433,3616,58166,59854,90623). One of its metabolites, trimethylamine N-oxide, can cause the urine, breath, and sweat to have a fishy odor (12756,58664).
General
...Orally, niacinamide is well tolerated in amounts typically found in food.
When used topically and orally in higher doses, niacinamide seems to be generally well tolerated.
Most Common Adverse Effects:
Orally: Dizziness, drowsiness, itching, gastrointestinal disturbances, headache, and rash.
Topically: Burning sensation, itching, and mild dermatitis.
Dermatologic ...Orally, large doses of niacinamide are associated with occasional reports of rashes, itching, and acanthosis nigricans (4880,11695,11697,14504,107709), though a meta-analysis of 19 clinical studies suggests that dermatological adverse event rates are similar between niacinamide and control (110497). Topically, application of niacinamide in a cream has been reported to cause a burning sensation, itching and pruritus, crusting, and mild dermatitis (93357,93360,110501,110498).
Endocrine ...Orally, niacinamide in high doses, 50 mg/kg daily, has been associated with modestly higher insulin requirements in patients with type 1 diabetes, when compared with taking niacinamide 25 mg/kg daily. Theoretically, high-dose niacinamide might increase insulin resistance, although to a lesser extent than niacin (4881,14512).
Gastrointestinal ...Orally, large doses of niacinamide can cause gastrointestinal disturbances including nausea, vomiting, heartburn, anorexia, epigastric pain, flatulence, and diarrhea (6243,11694,11695,11696,11697,107709,110497,113682).
Hematologic ...Orally, niacinamide supplementation might increase the risk for thrombocytopenia in patients undergoing hemodialysis (98940,107709). A meta-analysis of small clinical studies shows that taking niacinamide during hemodialysis to reduce phosphate levels is associated with a 2.8-fold increased risk for thrombocytopenia when compared with placebo. In one of the included studies, platelet levels returned to normal within 20 days after niacinamide discontinuation (98940).
Hepatic ...Orally, older reports of elevated liver function tests with high doses of niacinamide (3 grams or more daily) have raised concerns about liver toxicity. However, newer studies have not reported this concern; it is possible that some of these cases were due to contamination with niacin (4880,11694,11695,14503).
Neurologic/CNS ...Orally, large doses of niacinamide can cause dizziness, drowsiness, and headaches (11694,11695,11696,11697,107709).
General
...Orally, tyrosine seems to be well tolerated.
No serious adverse effects have been documented; however, a thorough evaluation of safety outcomes has not been conducted.
Most Common Adverse Effects:
Orally: Fatigue, headache, heartburn, and nausea.
Gastrointestinal ...Orally, tyrosine can cause nausea and heartburn when taken at a dose of 150 mg/kg (7211). Taking tyrosine 4 grams daily in combination with 5-hydroxytryptophan 800 mg and carbidopa 100 mg can cause diarrhea, nausea, and vomiting. These effects can be mitigated by lowering the dosage (918).
Musculoskeletal ...Orally, larger doses of tyrosine (150 mg/kg) can cause arthralgia, but this is uncommon (7211).
Neurologic/CNS ...Orally, larger doses of tyrosine (150 mg/kg) can cause headache and fatigue (7211). Taking a combination of tyrosine 4 grams, 5-hydroxytryptophan 800 mg, and carbidopa 100 mg can cause drowsiness and agitation. These effects can be mitigated by lowering the dosage (918).
General
...Orally, intramuscularly, and topically, vitamin B12 is generally well-tolerated.
Most Common Adverse Effects:
Intramuscular: Injection site reactions.
Serious Adverse Effects (Rare):
Intramuscularly: Severe hypokalemia has been rarely linked with correction of megaloblastic anemia with vitamin B12.
Cardiovascular ...In human clinical research, an intravenous loading dose of folic acid, vitamin B6, and vitamin B12, followed by daily oral administration after coronary stenting, increased restenosis rates (12150). Hypertension following intravenous administration of hydroxocobalamin has been reported in human research (82870,82864).
Dermatologic
...Orally or intramuscularly, vitamin B12 can cause allergic reactions such as rash, pruritus, erythema, and urticaria.
Theoretically, allergic reactions might be caused by the cobalt within the vitamin B12 molecule (82864,90373,90381,103974). In one case report, oral methylcobalamin resulted in contact dermatitis in a 59-year-old Japanese female with a cobalt allergy (103974). In another case report, a 69-year-old female developed a symmetrical erythematous-squamous rash for 5 years after oral vitamin B12 supplementation for 10 years. A patch test confirmed that the systemic allergic dermatitis was due to vitamin B12 supplementation, which resolved 3 months after discontinuation (114578).
Vitamin B12 (intramuscular or oral) has also been associated with at least 19 cases of acneiform eruptions which resolved upon discontinuation of vitamin B12 (90365,90369,90388). High-dose vitamin B12 (20 mcg daily) and vitamin B6 (80 mg daily) have been associated with cases of rosacea fulminans characterized by intense erythema with nodules, papules, and pustules. Symptoms may last up to four months after the supplement is stopped and can be treated with systemic corticosteroids and topical therapy (10998,82870,82871).
Gastrointestinal ...Intravenously, vitamin B12 (hydroxocobalamin) 2. 5-10 grams can cause nausea and dysphagia (82864).
Genitourinary ...Intravenously, vitamin B12 (hydroxocobalamin) 5-15 grams has been associated with chromaturia in clinical research (82870,82871,112282,112264).
Hematologic ...According to case report data, the correction of megaloblastic anemia with vitamin B12 may result in fatal hypokalemia (82914).
Musculoskeletal ...According to case report data, correction of megaloblastic anemia with vitamin B12 has precipitated gout in susceptible individuals (82879).
Neurologic/CNS ...Treatment with vitamin B12 has been rarely associated with involuntary movements in infants with vitamin B12 deficiency (90370,90385,90397). In some cases these adverse reactions were misdiagnosed as seizures or infantile tremor syndrome (90370,90385). These adverse reactions presented 2-5 days after treatment with vitamin B12 and resolved once vitamin B12 was discontinued (90370,90385,90397).
Oncologic ...Although some epidemiological research disagrees (9454), most research has found that elevated plasma levels of vitamin B12 are associated with an increased risk of various types of cancer, including lung and prostate cancers and solid tumors (50411,102383,107743). One study found, when compared with blood levels of vitamin B12 less than 1000 ng/mL, plasma vitamin B12 levels of at least 1000 ng/mL was strongly associated with the occurrence of solid cancer (107743). It is unclear if increased intake of vitamin B12, either through the diet or supplementation, directly affects the risk of cancer. It is possible that having cancer increases the risk of vitamin B12 elevation. However, one observational study has found that the highest quintile of dietary intake of vitamin B12 is associated with a 75% increased incidence of developing esophageal cancer when compared with the lowest quintile in never drinkers, but not drinkers (107147).
Renal ...There is a case report of oxalate nephropathy in a 54-year-old male which was determined to be related to the use of intravenous hydroxocobalamin as treatment for cyanide poisoning. Intermittent hemodialysis was started 5 days after admission, along with a low-oxalate diet, oral calcium acetate, and pyridoxine 5 mg/kg daily (107148). A review of the use of intravenous hydroxocobalamin for suspected cyanide poisoning in 21 intensive care units in France between 2011 and 2017 resulted in a 60% increased odds of acute kidney injury and a 77% increased odds of severe acute kidney injury in the first week. However, biopsies were not conducted and a direct link with use of hydroxocobalamin could not be made (107139).
Other ...Several studies have found that higher vitamin B12 levels may be associated with increased mortality or decreased survival rates in hospitalized elderly patients (82889,82812,82857,82895). Human research has also found a positive correlation between vitamin B12 status and all-cause mortality in Pima Indians with diabetes (82863).
General
...Orally or by injection, vitamin B6 is well tolerated in doses less than 100 mg daily.
Most Common Adverse Effects:
Orally or by injection: Abdominal pain, allergic reactions, headache, heartburn, loss of appetite, nausea, somnolence, vomiting.
Serious Adverse Effects (Rare):
Orally or by injection: Sensory neuropathy (high doses).
Dermatologic ...Orally, vitamin B6 (pyridoxine) has been linked to reports of skin and other allergic reactions and photosensitivity (8195,9479,90375). High-dose vitamin B6 (80 mg daily as pyridoxine) and vitamin B12 (20 mcg daily) have been associated with cases of rosacea fulminans characterized by intense erythema with nodules, papules, and pustules. Symptoms may persist for up to 4 months after the supplement is stopped, and may require treatment with systemic corticosteroids and topical therapy (10998).
Gastrointestinal ...Orally or by injection, vitamin B6 (pyridoxine) can cause nausea, vomiting, heartburn, abdominal pain, mild diarrhea, and loss of appetite (8195,9479,16306,83064,83103,107124,107127,107135). In a clinical trial, one patient experienced infectious gastroenteritis that was deemed possibly related to taking vitamin B6 (pyridoxine) orally up to 20 mg/kg daily (90796). One small case-control study has raised concern that long-term dietary vitamin B6 intake in amounts ranging from 3.56-6.59 mg daily can increase the risk of ulcerative colitis (3350).
Hematologic ...Orally or by injection, vitamin B6 (pyridoxine) can cause decreased serum folic acid concentrations (8195,9479). One case of persistent bleeding of unknown origin has been reported in a clinical trial for a patient who used vitamin B6 (pyridoxine) 100 mg twice daily on days 16 to 35 of the menstrual cycle (83103). It is unclear if this effect was due to vitamin B6 intake.
Musculoskeletal ...Orally or by injection, vitamin B6 (pyridoxine) can cause breast soreness or enlargement (8195).
Neurologic/CNS ...Orally or by injection, vitamin B6 (pyridoxine) can cause headache, paresthesia, and somnolence (8195,9479,16306). Vitamin B6 (pyridoxine) can also cause sensory neuropathy, which is related to daily dose and duration of intake. Doses exceeding 1000 mg daily or total doses of 1000 grams or more pose the most risk, although neuropathy can occur with lower daily or total doses as well (8195). The mechanism of the neurotoxicity is unknown, but is thought to occur when the liver's capacity to phosphorylate pyridoxine via the active coenzyme pyridoxal phosphate is exceeded (8204). Some researchers recommend taking vitamin B6 as pyridoxal phosphate to avoid pyridoxine neuropathy, but its safety is unknown (8204). Vitamin B6 (pyridoxine) neuropathy is characterized by numbness and impairment of the sense of position and vibration of the distal limbs, and a gradual progressive sensory ataxia (8196,10439). The syndrome is usually reversible with discontinuation of pyridoxine at the first appearance of neurologic symptoms. Residual symptoms have been reported in patients taking more than 2 grams daily for extended periods (8195,8196). Daily doses of 100 mg or less are unlikely to cause these problems (3094).
Oncologic ...In females, population research has found that a median intake of vitamin B6 1. 63 mg daily is associated with a 3.6-fold increased risk of rectal cancer when compared with a median intake of 1.05 mg daily (83024). A post-hoc subgroup analysis of results from clinical research in adults with a history of recent stroke or ischemic attack suggests that taking folic acid, vitamin B12, and vitamin B6 does not increase cancer risk overall, although it was associated with an increased risk of cancer in patients who also had diabetes (90378). Also, in patients with nasopharyngeal carcinoma, population research has found that consuming at least 8.6 mg daily of supplemental vitamin B6 during treatment was associated with a lower overall survival rate over 5 years, as well as a reduced progression-free survival, when compared with non-users and those with intakes of up to 8.6 mg daily (107134).
General
...Orally, intravenously, and topically, vitamin C is well-tolerated.
Most Common Adverse Effects:
Orally: Abdominal cramps, esophagitis, heartburn, headache, osmotic diarrhea, nausea, vomiting. Kidney stones have been reported in those prone to kidney stones. Adverse effects are more likely to occur at doses above the tolerable upper intake level of 2 grams daily.
Topically: Irritation and tingling.
Serious Adverse Effects (Rare):
Orally: There have been rare case reports of carotid inner wall thickening after large doses of vitamin C.
Intravenously: There have been case reports of hyperoxalosis and oxalate nephropathy following high-dose infusions of vitamin C.
Cardiovascular
...Evidence from population research has found that high doses of supplemental vitamin C might not be safe for some people.
In postmenopausal adults with diabetes, supplemental vitamin C intake in doses greater than 300 mg per day is associated with increased risk of cardiovascular mortality. However, dietary intake of vitamin C is not associated with this risk. Also, vitamin C intake is not associated with an increased risk of cardiovascular mortality in patients without diabetes (12498).
Oral supplementation with vitamin C has also been associated with an increased rate of carotid inner wall thickening in men. There is preliminary evidence that supplemental intake of vitamin C 500 mg daily for 18 months can cause a 2.5-fold increased rate of carotid inner wall thickening in non-smoking men and a 5-fold increased rate in men who smoked. The men in this study were 40-60 years old (1355). This effect was not associated with vitamin C from dietary sources (1355).
There is also some concern that vitamin C may increase the risk of hypertension in some patients. A meta-analysis of clinical research suggests that, in pregnant patients at risk of pre-eclampsia, oral intake of vitamin C along with vitamin E increases the risk of gestational hypertension (83450). Other clinical research shows that oral intake of vitamin C along with grape seed polyphenols can increase both systolic and diastolic blood pressure in hypertensive patients (13162). Three cases of transient hypotension and tachycardia during intravenous administration of vitamin C have also been reported (114490).
Dental ...Orally, vitamin C, particularly chewable tablets, has been associated with dental erosion (83484).
Dermatologic ...Topically, vitamin C might cause tingling or irritation at the site of application (6166). A liquid containing vitamin C 20%, red raspberry leaf cell culture extract 0.0005%, and vitamin E 1% (Antioxidant and Collagen Booster Serum, Max Biocare Pty Ltd.) has been reported to cause mild tingling and skin tightness (102355). It is unclear if these effects are due to vitamin C, the other ingredients, or the combination.
Gastrointestinal ...Orally, the adverse effects of vitamin C are dose-related and include nausea, vomiting, esophagitis, heartburn, abdominal cramps, gastrointestinal obstruction, and diarrhea. Doses greater than the tolerable upper intake level (UL) of 2000 mg per day can increase the risk of adverse effects such as osmotic diarrhea and severe gastrointestinal upset (3042,4844,96707,104450,114493,114490). Mineral forms of vitamin C, such as calcium ascorbate (Ester-C), seem to cause fewer gastrointestinal adverse effects than regular vitamin C (83358). In a case report, high dose intravenous vitamin C was associated with increased thirst (96709).
Genitourinary ...Orally, vitamin C may cause precipitation of urate, oxalate, or cysteine stones or drugs in the urinary tract (10356). Hyperoxaluria, hyperuricosuria, hematuria, and crystalluria have occurred in people taking 1 gram or more per day (3042,90943). Supplemental vitamin C over 250 mg daily has been associated with higher risk for kidney stones in males. There was no clear association found in females, but the analysis might not have been adequately powered to evaluate this outcome (104029). In people with a history of oxalate kidney stones, supplemental vitamin C 1 gram per day appears to increase kidney stone risk by 40% (12653). A case of hematuria, high urine oxalate excretion, and the presence of a ureteral stone has been reported for a 9-year-old male who had taken about 3 grams of vitamin C daily since 3 years of age. The condition resolved with cessation of vitamin C intake (90936).
Hematologic ...Prolonged use of large amounts of vitamin C can result in increased metabolism of vitamin C; subsequent reduction in vitamin C intake may precipitate the development of scurvy (15). In one case, a patient with septic shock and a large intraperitoneal hematoma developed moderate hemolysis and increased methemoglobin 12 hours after a high-dose vitamin C infusion. The patient received a blood transfusion and the hemolysis resolved spontaneously over 48 hours (112479).
Neurologic/CNS ...Orally, the adverse effects of vitamin C are dose-related and include fatigue, headache, insomnia, and sleepiness (3042,4844,83475,83476).
Renal ...Hyperoxalosis and oxalate nephropathy have been reported following high-dose infusions of vitamin C. Hyperoxalosis and acute kidney failure contributed to the death of a 76-year-old patient with metastatic adenocarcinoma of the lung who received 10 courses of intravenous infusions containing vitamins, including vitamin C and other supplements over a period of 1 month. Dosages of vitamin C were not specified but were presumed to be high-dose (106618). In another case, a 34-year-old patient with a history of kidney transplant and cerebral palsy was found unresponsive during outpatient treatment for a respiratory tract infection. The patient was intubated for acute hypoxemic respiratory failure, initiated on vasopressors, hydrocortisone, and antibacterial therapy, and received 16 doses of vitamin C 1.5 grams. Serum creatinine level peaked at greater than 3 times baseline and the patient required hemodialysis for oliguria and uncontrolled acidosis. Kidney biopsy revealed oxalate nephropathy with concomitant drug-induced interstitial nephritis (106625). In another case, a 41-year-old patient with a history of kidney transplant presented with fever, nausea, and decreased urine output 4 days after receiving intravenous vitamin C 7 grams for urothelial carcinoma. Serum creatinine levels increased from 1.7 mg/dL to 7.3 mg/dL over those 4 days, and hemodialysis was initiated 3 days after admission due to anuria. Renal biopsy confirmed the diagnosis of acute oxalate nephropathy (109962).
Other ...Intravenously, hypernatremia and falsely elevated ketone levels is reported in a patient with septic shock and chronic kidney disease after a high-dose vitamin C infusion. The hypernatremia resolved over 24 hours after cessation of the infusion (112479).
