Roasted Chicory root • Black Tea • Roasted and Raw Yerba Mate • Carob • Cinnamon • Roasted Dandelion root • Indian Sarsaparilla root • Licorice root • Natural Flavor.
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Below is general information about the effectiveness of the known ingredients contained in the product Mu Zest Tea. 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
Below is general information about the safety of the known ingredients contained in the product Mu Zest Tea. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
LIKELY SAFE ...when consumed orally in moderate amounts (1452,9222,9223,9224,9228,9233,9234,9235,9236,36376)(36426,36434,36436,36581). Black tea contains caffeine. According to a review by Health Canada, and a subsequent large meta-analysis conducted in the US, drinking up to 4 cups of black tea daily, or approximately 400 mg of caffeine, is 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).
POSSIBLY UNSAFE ...when consumed orally long term or in high amounts. Black tea contains a significant amount of caffeine. Chronic use, especially in large amounts, can produce tolerance, habituation, psychological dependence, and other significant adverse effects. Doses of caffeine greater than 600 mg per day, or approximately 6 cups of black tea, have been associated with significant adverse effects such as tachyarrhythmias and sleep disturbances (11832). These effects would not be expected to occur with the consumption of decaffeinated black tea. 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 black tea, 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.
LIKELY UNSAFE ...when consumed orally in very high amounts. The fatal acute oral dose of caffeine is estimated to be 10-14 grams (150-200 mg per kilogram). Serious toxicity can occur at lower doses depending on variables in caffeine sensitivity such as smoking, age, prior caffeine use, etc. (11832).
CHILDREN: POSSIBLY SAFE
when used in food and beverage amounts (4912,11833).
PREGNANCY: POSSIBLY SAFE
when used orally in moderate amounts.
Due to the caffeine content of black tea, mothers should closely monitor their intake to ensure moderate consumption. Caffeine crosses the human placenta but is not considered a teratogen. Fetal blood concentrations of caffeine approximate maternal concentrations (4260). The use of caffeine during pregnancy is controversial; however, moderate consumption has not been associated with clinically important adverse fetal effects (2708,2709,2710,2711,9606,11733,16014,16015,37802,37584). In some studies, consuming amounts over 200 mg daily is associated with a significantly increased risk of miscarriage (16014). This increased risk may be most likely to occur in females 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, most healthy patients can safely consume doses up to 300 mg daily during pregnancy without an increased risk of spontaneous abortion, stillbirth, preterm birth, fetal growth retardation, or congenital malformations (11733,98806). Advise keeping caffeine consumption below 300 mg daily. This is similar to the amount of caffeine in about 3 cups of black tea. 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 black tea, 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: POSSIBLY UNSAFE
when used orally in large amounts.
Caffeine from black tea crosses the placenta, producing fetal blood concentrations similar to maternal levels (4260). Consumption of caffeine in amounts over 300 mg daily is associated with a significantly increased risk of miscarriage (16014,98806). Advise keeping caffeine consumption from all sources below 300 mg daily. This is similar to the amount of caffeine in about 3 cups of black tea. 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 (2709,2711,24995,24998,37561,37898,38012,38186,38199,38212)(38285,38290). Preliminary evidence from a population study also suggests that increasing consumption of black tea might increase the risk of spina bifida (15112); however, this finding needs to be verified with additional research.
Cohort studies suggest that consuming large amounts of caffeine during pregnancy may reduce the height and weight of the infants born as they grow up. 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).
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 black tea, 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.
More evidence is needed to determine the safety of using black tea during pregnancy. For now, advise avoidance of large quantities of black tea during pregnancy.
LACTATION: POSSIBLY SAFE
when used orally in moderate amounts.
Due to the caffeine content of black tea, caffeine intake should be closely monitored. Breast milk concentrations of caffeine are thought to be approximately 50% of maternal serum concentrations. Minimal consumption would likely result in limited exposure to a nursing infant (9892).
LACTATION: POSSIBLY UNSAFE
when used orally in large amounts.
Consumption of black tea might cause irritability and increased bowel activity in nursing infants (6026). Black tea might also interfere with iron metabolism and folic acid bioavailability in nursing infants (631,53782). Large doses or excessive intake of black tea should be avoided during lactation.
LIKELY SAFE ...when used orally in amounts commonly found in foods. Carob has Generally Recognized as Safe (GRAS) status (4912).
POSSIBLY SAFE ...when used orally in medicinal amounts, short-term. Carob fiber containing 80% polyphenols (Exxenterol, Puleva Biotech SA) has been used with apparent safety in doses of up to 8 grams daily for up to 12 weeks (97846). A beverage made with carob pod extract (Fruit Up, Wild-Valencia SAU) has been used with apparent safety at a dose of 500 mL daily for up to 12 weeks (97849). Carob pod powder has been safely used in doses up to 1500 mg daily for up to 90 days (111127).
CHILDREN: POSSIBLY SAFE
when used in full-term infants.
Carob-based milk thickeners have been used with apparent safety in full-term infants as an additive in infant formula (39972,39991,104239,111128).
CHILDREN: POSSIBLY UNSAFE
when used in preterm infants.
A carob-based milk thickener (Carobel) has been associated with necrotizing enterocolitis leading to death in two low birth-weight infants (39991).
PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.
LIKELY SAFE ...when consumed in amounts commonly found in food. Chicory and chicory extract have Generally Recognized as Safe (GRAS) status in the US (4912).
POSSIBLY SAFE ...when used orally in medicinal amounts, short-term. Chicory root extract has been used with apparent safety at doses of 600 mg three times daily for one month (93647). Chicory seed has been used with apparent safety as a hot water infusion of 4.5 grams twice daily for 12 weeks (102350). There is insufficient reliable information available about the safety of chicory when used orally, long-term, or when used topically.
PREGNANCY: POSSIBLY UNSAFE
when used orally in excessive amounts.
Chicory may induce menstruation or miscarriage (19).
LACTATION:
Insufficient reliable information available; avoid using.
LIKELY SAFE ...when used orally in amounts commonly found in foods. Dandelion has Generally Recognized As Safe (GRAS) status in the US (4912).
POSSIBLY SAFE ...when used orally and appropriately in medicinal amounts (12). There is insufficient reliable information available about the safety of dandelion when used topically.
PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using amounts greater than those in foods.
LIKELY SAFE ...when used orally in amounts commonly found in foods. Licorice has Generally Recognized as Safe (GRAS) status in the US (4912).
POSSIBLY SAFE ...when licorice products that do not contain glycyrrhizin (deglycyrrhizinated licorice) are used orally and appropriately for medicinal purposes. Licorice flavonoid oil 300 mg daily for 16 weeks, and deglycyrrhizinated licorice products in doses of up to 4.5 grams daily for up to 16 weeks, have been used with apparent safety (6196,11312,11313,17727,100984,102960). ...when licorice products containing glycyrrhizin are used orally in low doses, short-term. Licorice extract 272 mg, containing glycyrrhizin 24.3 mg, has been used daily with apparent safety for 6 months (102961). A licorice extract 1000 mg, containing monoammonium glycyrrhizinate 240 mg, has been used daily with apparent safety for 12 weeks (110320). In addition, a syrup providing licorice extract 750 mg has been used twice daily with apparent safety for 5 days (104558). ...when applied topically. A gel containing 2% licorice root extract has been applied to the skin with apparent safety for up to 2 weeks. (59732). A mouth rinse containing 5% licorice extract has been used with apparent safety four times daily for up to one week (104564).
POSSIBLY UNSAFE ...when licorice products containing glycyrrhizin are used orally in large amounts for several weeks, or in smaller amounts for longer periods of time. The European Scientific Committee on Food recommends that a safe average daily intake of glycyrrhizin should not exceed 10 mg (108577). In otherwise healthy people, consuming glycyrrhizin daily for several weeks or longer can cause severe adverse effects including pseudohyperaldosteronism, hypertensive crisis, hypokalemia, cardiac arrhythmias, and cardiac arrest. Doses of 20 grams or more of licorice products, containing at least 400 mg glycyrrhizin, are more likely to cause these effects; however, smaller amounts have also caused hypokalemia and associated symptoms when taken for months to years (781,3252,15590,15592,15594,15596,15597,15599,15600,16058)(59731,59740,59752,59785,59786,59787,59792,59795,59805,59811)(59816,59818,59820,59822,59826,59828,59849,59850,59851,59867)(59882,59885,59888,59889,59895,59900,59906,97213,110305). In patients with hypertension, cardiovascular or kidney conditions, or a high salt intake, as little as 5 grams of licorice product or 100 mg glycyrrhizin daily can cause severe adverse effects (15589,15593,15598,15600,59726).
PREGNANCY: UNSAFE
when used orally.
Licorice has abortifacient, estrogenic, and steroid effects. It can also cause uterine stimulation. Heavy consumption of licorice, equivalent to 500 mg of glycyrrhizin per week (about 250 grams of licorice per week), during pregnancy seems to increase the risk of delivery before gestational age of 38 weeks (7619,10618). Furthermore, high intake of glycyrrhizin, at least 500 mg per week, during pregnancy is associated with increased salivary cortisol levels in the child by the age of 8 years. This suggests that high intake of licorice during pregnancy may increase hypothalamic-pituitary-adrenocortical axis activity in the child (26434); avoid using.
LACTATION:
Insufficient reliable information available; avoid using.
LIKELY SAFE ...when used orally in amounts commonly found in foods. Sarsaparilla has Generally Recognized As Safe (GRAS) status for use in foods in the US (4912). There is insufficient reliable information available about the safety of sarsaparilla when taken orally in medicinal amounts.
PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.
POSSIBLY SAFE ...when used orally and appropriately, short-term (11866). Yerba mate has been safely used in doses of 3 grams daily for up to 12 weeks (92152,96469,96470).
POSSIBLY UNSAFE ...when yerba mate is used orally in large amounts or for prolonged periods of time. Drinking approximately 1-2 liters, or 4-8 cups, of yerba mate daily is associated with an increased risk of cancer, including esophageal, stomach, kidney, bladder, cervical, prostate, lung, renal cell, and possibly laryngeal and mouth cancer (1528,1529,1530,1531,11863,11864,92150). Yerba mate also contains caffeine. Acute use of high doses of caffeine (more than 400 mg per day), which is found in more than 8-10 cups of yerba mate, has been associated with significant adverse effects such as tachyarrhythmia and sleep disturbances (11832). Drinking yerba mate in amounts greater than 12-15 cups daily (about 600 mg caffeine) short-term or long-term can also cause caffeinism with symptoms of anxiety possibly progressing to delirium and agitation. Chronic use of caffeine, especially in large amounts, can sometimes produce tolerance, habituation, and psychological dependence (3719). Abrupt discontinuance of caffeine can cause physical withdrawal symptoms (11733). 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 yerba mate, 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.
CHILDREN: POSSIBLY UNSAFE
when used orally.
Yerba mate is associated with an increased risk of cancer, including esophageal, kidney, bladder, cervical, prostate, lung, and possibly mouth and laryngeal cancer (1528,1529,1530,1531,11863,11864,92150).
PREGNANCY: POSSIBLY UNSAFE
when used orally.
Yerba mate is associated with an increased risk of cancer, including esophageal, kidney, bladder, cervical, prostate, lung, renal cell, and possibly mouth and laryngeal cancer (1528,1529,1530,1531,11863,11864,92150,86595,86614,86700,86701). However, teratogenic studies have not been performed. Yerba mate also contains caffeine. Caffeine crosses the placenta, producing fetal blood concentrations similar to parental levels. According to a review by Health Canada, and a subsequent large meta-analysis conducted in the US, most healthy pregnant patients can safely consume caffeine in doses up to 300 mg daily without an increased risk of spontaneous abortion, stillbirth, preterm birth, fetal growth retardation, or congenital malformations (11733,98806). It is generally recommended to avoid consuming more than 300 mg of caffeine daily, or around 6-7 cups of yerba mate daily, when pregnant (2708). High doses of caffeine throughout pregnancy have resulted in symptoms of caffeine withdrawal in newborn infants (9891,86618). Caffeine in doses of greater than 300 mg daily has also been associated with spontaneous abortion, premature delivery, and low birth weight (2709,2711), although one retrospective study found that consuming yerba mate tea during pregnancy was not associated with preterm or small for gestational age births (13113). However, this study did not consider the amount of yerba mate or caffeine consumed, only the frequency of consumption. Some research has found that intrauterine exposure to even modest amounts of caffeine, based on maternal blood levels during the first trimester, is associated with a shorter stature in children ages 4-8 years (109846).
LACTATION: POSSIBLY UNSAFE
when used orally.
Yerba mate is associated with an increased risk of cancer, including esophageal, kidney, bladder, cervical, prostate, lung, renal cell, and possibly mouth and laryngeal cancer (1528,1529,1530,1531,11863,11864,92150). Whether carcinogenic constituents of yerba mate are transferred via breast milk is unknown. Yerba mate contains caffeine. Consumption of yerba mate might cause irritability and increased bowel activity in nursing infants (6026).
Below is general information about the interactions of the known ingredients contained in the product Mu Zest Tea. 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, black tea might decrease the vasodilatory effects of adenosine and interfere with its use prior to stress testing.
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Black tea contains caffeine. Caffeine is a competitive inhibitor of adenosine at the cellular level (38172). 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, black tea may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
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Theoretically, taking black tea with antidiabetes drugs might interfere with blood glucose control.
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Theoretically, concomitant use of large amounts of black tea might increase cardiac inotropic effects of beta-agonists.
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Black tea contains caffeine. Caffeine can increase cardiac inotropic effects of beta-agonists (15).
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Theoretically, black tea might reduce the effects of carbamazepine and increase the risk for convulsion.
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Black tea contains caffeine. Animal research suggests that 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, concomitant use might increase the effects and adverse effects of caffeine in black tea.
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Theoretically, black tea might increase the levels and adverse effects of clozapine and acutely exacerbate psychotic symptoms.
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Concomitant administration of black tea and clozapine might theoretically cause acute exacerbation of psychotic symptoms due to the caffeine in black tea. 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 be more sensitive to the interaction between clozapine and caffeine (13741).
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Theoretically, concomitant use might increase the effects and adverse effects of caffeine found in black tea.
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Theoretically, concomitant use might increase the levels and adverse effects of caffeine.
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Black tea contains caffeine. Caffeine is metabolized by CYP1A2 (3941,5051,11741,23557,23573,23580,24958,24959,24960,24962), (24964,24965,24967,24968,24969,24971,38081,48603). Theoretically, drugs that inhibit CYP1A2 may decrease the clearance rate of caffeine from black tea and increase caffeine levels.
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Theoretically, black tea might decrease the vasodilatory effects of dipyridamole and interfere with its use prior to stress testing.
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Black tea contains 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 black tea, 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 risk of adverse effects from caffeine.
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Black tea contains caffeine. In human research, disulfiram decreases the clearance and increases the half-life of caffeine (11840).
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Theoretically, using black tea with diuretic drugs might increase the risk of hypokalemia.
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Theoretically, concomitant use might increase the risk for simulant adverse effects.
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Black tea contains 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 (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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Black tea contains caffeine. Estrogen inhibits caffeine metabolism (2714).
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Theoretically, black tea might reduce the effects of ethosuximide and increase the risk for convulsions.
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Black tea contains caffeine. Animal research suggests that caffeine 92.4 mg/kg can decrease the anticonvulsant activity of ethosuximide (23560). However, this effect has not been observed in humans.
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Theoretically, black tea might reduce the effects of felbamate and increase the risk for convulsions.
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Black tea contains caffeine. Animal research suggests that a high dose of caffeine 161.7 mg/kg can decrease the anticonvulsant activity of felbamate (23563). However, this effect has not been observed in humans.
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Theoretically, fluconazole might increase the levels and adverse effects of caffeine.
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Theoretically, black tea might decrease the metabolism of flurbiprofen.
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In vitro research shows that black tea decreases the metabolism of flurbiprofen, a cytochrome P450 2C9 (CYP2C9) substrate, by about 10%. However, clinical research suggests that drinking black tea does not significantly affect flurbiprofen plasma levels, metabolism, or elimination (11094).
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Theoretically, black tea might increase the levels and adverse effects of flutamide.
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Black tea contains caffeine. In vitro evidence suggests that caffeine can inhibit the metabolism of flutamide (23553). Theoretically, concomitant use of caffeine and flutamide might increase serum concentrations of flutamide and increase the risk of adverse effects.
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Theoretically, fluvoxamine might increase the levels and adverse effects of caffeine.
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Theoretically, abrupt black tea withdrawal might increase the levels and adverse effects of lithium.
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Theoretically, metformin might increase the levels and adverse effects of caffeine.
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Black tea contains caffeine. Animal research suggests that metformin can reduce caffeine metabolism (23571). Theoretically, concomitant use can increase caffeine serum concentrations and the risk of caffeine adverse effects.
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Theoretically, methoxsalen might increase the levels and adverse effects of caffeine.
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Black tea contains caffeine. Methoxsalen can reduce caffeine metabolism (23572). Concomitant use can increase caffeine serum concentrations and the risk of caffeine adverse effects.
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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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Black tea contains caffeine. 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 caffeinate coffee and took the MAOI tranylcypromine presented with severe hypertension (91086). Hypertension was resolved after the patients switched to drinking decaffeinated coffee.
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Theoretically, concomitant use might increase the risk of hypertension.
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Black tea contains 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, black tea might reduce the absorption of organic anion-transporting polypeptide (OATP) substrates.
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In vitro, black tea extract inhibits organic anion-transporting polypeptide (OATP)2B1. OATP2B1 is expressed in the small intestine and liver and is responsible for the uptake of drugs and other compounds. In an animal model, black tea extract was found to inhibit the absorption of rosuvastatin, a substrate of OATP2B1 (104584). However, this effect has not been reported in humans.
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Theoretically, black tea might decrease the effects of pentobarbital.
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Black tea contains caffeine. Theoretically, caffeine might negate the hypnotic effects of pentobarbital (13742).
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Theoretically, black tea 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. Also, black tea may bind to phenothiazines and reduce their absorption.
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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, black tea might reduce the effects of phenytoin and increase the risk for convulsions.
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Theoretically, black tea might increase the levels and clinical effects of pioglitazone.
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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.
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Black tea contains 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 decrease the levels and clinical effects of rosuvastatin.
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In animals, taking black tea extract along with rosuvastatin reduces plasma levels of rosuvastatin by approximately 48%. In vitro, black tea extract was found to inhibit organic anion-transporting polypeptide (OATP)2B1, a protein expressed in the small intestine that is responsible for the uptake of rosuvastatin and other compounds (104584). This effect has not been reported in humans.
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Theoretically, concomitant use might increase stimulant adverse effects.
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Black tea contains 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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Black tea contains caffeine. Terbinafine decreases the clearance of intravenous caffeine by 19% (11740).
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Theoretically, black tea might increase the levels and adverse effects of theophylline.
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Theoretically, black tea might increase the levels and adverse effects of tiagabine.
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Black tea contains caffeine. 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.
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Black tea contains caffeine. 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, TCAs might bind with black tea constituents when taken at the same time.
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Theoretically, black tea might reduce the effects of valproate and increase the risk for convulsions.
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Theoretically, concomitant use might increase the levels and adverse effects of caffeine.
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Black tea contains caffeine. Verapamil increases plasma caffeine concentrations by 25% (11741).
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Consuming large amounts of black tea might decrease the effects of warfarin.
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In one case, a 67-year-old female who took warfarin and who regularly consumed large amounts of black tea had a stable international normalized ratio (INR) of 1.7 to 2.7. However, the INR increased to 5 when tea consumption was discontinued. It is thought that the vitamin K content of black tea may have reduced the effects of warfarin (16902). Monitor patients carefully who start or discontinue drinking black tea while taking warfarin.
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Theoretically, carob might also impair the absorption of oral drugs.
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Theoretically, chicory might increase the risk of hypoglycemia when taken with antidiabetes drugs.
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Theoretically, taking dandelion root along with anticoagulant or antiplatelet drugs might increase the risk of bruising and bleeding.
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In vitro research suggests that dandelion root inhibits platelet aggregation (18291).
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Theoretically, dandelion might increase the risk for hypoglycemia when used with antidiabetes drugs.
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Laboratory research suggests that dandelion extract may have moderate alpha-glucosidase inhibitor activity and might also increase insulin secretion (13474,90926). Also, in a case report, a 58-year-old woman with type 2 diabetes who was being treated with insulin developed hypoglycemia 2 weeks after beginning to eat salads containing dandelion (46960).
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Theoretically, dandelion might increase levels of drugs metabolized by CYP1A2.
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Laboratory research suggests that dandelion might inhibit CYP1A2 (12734). So far, this interaction has not been reported in humans. However, until more is known, watch for an increase in the levels of drugs metabolized by CYP1A2 in patients taking dandelion.
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Theoretically, dandelion might increase the clearance of drugs that are UDP-glucuronosyltransferase substrates.
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There is some preliminary evidence that dandelion might induce UDP-glucuronosyltransferase, a phase II enzyme (12734).
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Theoretically, through diuretic effects, dandelion might reduce excretion and increase levels of lithium.
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Animal research suggests that dandelion has diuretic properties (13475). As diuretics can increase serum lithium levels, the dose of lithium might need to be decreased when taken with dandelion.
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Theoretically, dandelion might increase the risk of hyperkalemia when taken with potassium-sparing diuretics.
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Dandelion contains significant amounts of potassium (13465).
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Theoretically, dandelion might lower fluoroquinolone levels.
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Animal research shows that dandelion reduces absorption of ciprofloxacin and can lower levels by 73% (13477). However, this effect has not been reported in humans.
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Theoretically, licorice might reduce the effects of antihypertensive drugs.
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Theoretically, licorice might reduce the effects of cisplatin.
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In animal research, licorice diminished the therapeutic efficacy of cisplatin (59763).
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Theoretically, concomitant use of licorice and corticosteroids might increase the side effects of corticosteroids.
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Case reports suggest that concomitant use of licorice and oral corticosteroids, such as hydrocortisone, can potentiate the duration of activity and increase blood levels of corticosteroids (3252,12672,20040,20042,48429,59756). Additionally, in one case report, a patient with neurogenic orthostatic hypertension stabilized on fludrocortisone 0.1 mg twice daily developed pseudohyperaldosteronism after recent consumption of large amounts of black licorice (108568).
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Theoretically, licorice might decrease the levels and clinical effects of CYP1A2 substrates.
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In vitro research shows that licorice induces CYP1A2 enzymes (111404).
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Theoretically, licorice might increase levels of drugs metabolized by CYP2B6.
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In vitro research shows that licorice extract and glabridin, a licorice constituent, inhibit CYP2B6 isoenzymes (10300,94822). Licorice extract from the species G. uralensis seems to inhibit CYP2B6 isoenzymes to a greater degree than G. glabra extract in vitro (94822). Theoretically, these species of licorice might increase levels of drugs metabolized by CYP2B6; however, these interactions have not yet been reported in humans.
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Theoretically, licorice might increase levels of drugs metabolized by CYP2C19.
Details
In vitro, licorice extracts from the species G. glabra and G. uralensis inhibit CYP2C19 isoenzymes in vitro (94822). Theoretically, these species of licorice might increase levels of drugs metabolized by CYP2C19; however, this interaction has not yet been reported in humans.
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Theoretically, licorice might increase levels of drugs metabolized by CYP2C8.
Details
In vitro, licorice extract from the species G. glabra and G. uralensis inhibits CYP2C8 isoenzymes (94822). Theoretically, these species of licorice might increase levels of drugs metabolized by CYP2C8; however, this interaction has not yet been reported in humans.
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Theoretically, licorice might increase or decrease levels of drugs metabolized by CYP2C9.
Details
There is conflicting evidence about the effect of licorice on CYP2C9 enzyme activity. In vitro research shows that extracts from the licorice species G. glabra and G. uralensis moderately inhibit CYP2C9 isoenzymes (10300,94822). However, evidence from an animal model shows that licorice extract from the species G. uralensis can induce hepatic CYP2C9 activity (14441). Until more is known, licorice should be used cautiously in people taking CYP2C9 substrates.
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Theoretically, licorice might increase or decrease levels of drugs metabolized by CYP3A4.
Details
Pharmacokinetic research shows that the licorice constituent glycyrrhizin, taken in a dosage of 150 mg orally twice daily for 14 days, modestly decreases the area under the concentration-time curve of midazolam by about 20%. Midazolam is a substrate of CYP3A4, suggesting that glycyrrhizin modestly induces CYP3A4 activity (59808). Animal research also shows that licorice extract from the species G. uralensis induces CYP3A4 activity (14441). However, licorice extract from G. glabra species appear to inhibit CYP3A4-induced metabolism of testosterone in vitro. It is thought that the G. glabra inhibits CYP3A4 due to its constituent glabridin, which is a moderate CYP3A4 inhibitor in vitro and not present in other licorice species (10300,94822). Until more is known, licorice should be used cautiously in people taking CYP3A4 substrates.
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Theoretically, concomitant use of licorice with digoxin might increase the risk of cardiac toxicity.
Details
Overuse or misuse of licorice with cardiac glycoside therapy might increase the risk of cardiac toxicity due to potassium loss (10393).
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Theoretically, concomitant use of licorice with diuretic drugs might increase the risk of hypokalemia.
Details
Overuse of licorice might compound diuretic-induced potassium loss (10393,20045,20046,59812). In one case report, a 72-year-old male with a past medical history of hypertension, type 2 diabetes, hyperlipidemia, arrhythmia, stroke, and hepatic dysfunction was hospitalized with severe hypokalemia and uncontrolled hypertension due to pseudohyperaldosteronism. This was thought to be provoked by concomitant daily consumption of a product containing 225 mg of glycyrrhizin, a constituent of licorice, and hydrochlorothiazide 12.5 mg for 1 month (108577).
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Theoretically, licorice might increase or decrease the effects of estrogen therapy.
Details
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Theoretically, loop diuretics might increase the mineralocorticoid effects of licorice.
Details
Theoretically, loop diuretics might enhance the mineralocorticoid effects of licorice by inhibiting the enzyme that converts cortisol to cortisone; however, bumetanide (Bumex) does not appear to have this effect (3255).
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Theoretically, licorice might increase levels of methotrexate.
Details
Animal research suggests that intravenous administration of glycyrrhizin, a licorice constituent, and high-dose methotrexate may delay methotrexate excretion and increase systemic exposure, leading to transient elevations in liver enzymes and total bilirubin (108570). This interaction has not yet been reported in humans.
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Theoretically, licorice might decrease levels of midazolam.
Details
In humans, the licorice constituent glycyrrhizin appears to moderately induce the metabolism of midazolam (59808). This is likely due to induction of cytochrome P450 3A4 by licorice. Until more is known, licorice should be used cautiously in people taking midazolam.
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Theoretically, licorice might decrease the absorption of P-glycoprotein substrates.
Details
In vitro research shows that licorice can increase P-glycoprotein activity (104561).
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Theoretically, licorice might decrease plasma levels and clinical effects of paclitaxel.
Details
Multiple doses of licorice taken concomitantly with paclitaxel might reduce the effectiveness of paclitaxel. Animal research shows that licorice 3 grams/kg given orally for 14 days before intravenous administration of paclitaxel decreases the exposure to paclitaxel and increases its clearance. Theoretically, this occurs because licorice induces cytochrome P450 3A4 enzymes, which metabolize paclitaxel. Notably, a single dose of licorice did not affect exposure or clearance of paclitaxel (102959).
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Theoretically, licorice might decrease plasma levels and clinical effects of warfarin.
Details
Licorice seems to increase metabolism and decrease levels of warfarin in animal models. This is likely due to induction of cytochrome P450 2C9 (CYP2C9) metabolism by licorice (14441). Advise patients taking warfarin to avoid taking licorice.
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Theoretically, concomitant use of sarsaparilla with digoxin might increase the risk of cardiac toxicity.
Details
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Theoretically, sarsaparilla might increase the effects and adverse effects of lithium.
Details
Sarsaparilla is thought to have diuretic properties (11). Due to these effects, sarsaparilla might reduce excretion and increase levels of lithium. The dose of lithium might need to be decreased.
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Theoretically, the caffeine in yerba mate might decrease the vasodilatory effects of adenosine and interfere with its use prior to stress testing.
Details
Yerba mate contains caffeine. 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). Still, some researchers recommend that methylxanthines, such as caffeine, as well as methylxanthine-containing products, should 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 of alcohol and yerba mate might increase levels and adverse effects of the caffeine in yerba mate.
Details
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Theoretically, the caffeine in yerba mate may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Details
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Theoretically, taking yerba mate with antidiabetes drugs might interfere with blood glucose control.
Details
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Theoretically, the caffeine in yerba mate might reduce the efficacy of benzodiazepines.
Details
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Theoretically, the caffeine in yerba mate might increase the cardiac inotropic effects of beta-agonists, especially if taken in large amounts.
Details
Yerba mate contains caffeine. Caffeine can increase cardiac inotropic effects of beta-agonists (15).
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Theoretically, the caffeine in yerba mate might reduce the effects of carbamazepine and increase the risk for convulsions.
Details
Yerba mate contains caffeine. Animal research suggests that caffeine can lower the anticonvulsant effects of carbamazepine and can induce seizures when taken in doses above 400 mg/kg (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 two-fold in healthy individuals (23562).
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Theoretically, cimetidine might increase the levels and adverse effects of the caffeine contained in yerba mate.
Details
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Theoretically, the caffeine in yerba mate might increase the levels and adverse effects of clozapine and acutely exacerbate psychotic symptoms.
Details
Yerba mate contains caffeine. 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).
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Theoretically, contraceptive drugs might increase the levels and adverse effects of the caffeine contained in yerba mate.
Details
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Theoretically, concomitant use of CYP1A2 inhibitors and yerba mate might increase levels and adverse effects of the caffeine in yerba mate.
Details
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Theoretically, yerba mate might increase the levels and clinical effects of CYP3A4 substrates.
Details
In vitro research shows that yerba mate extract inhibits CYP3A4 enzymes (105811). Theoretically, taking yerba mate may increase levels and adverse effects of CYP3A4 substrates.
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Theoretically, the caffeine in yerba mate might decrease the vasodilatory effects of dipyridamole and interfere with its use prior to stress testing.
Details
Yerba mate contains caffeine. Caffeine inhibits dipyridamole-induced vasodilation (11770,11772). Still, some researchers recommend that methylxanthines, such as caffeine, as well as methylxanthine-containing products, should be stopped 24 hours prior to pharmacological stress (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 the caffeine in yerba mate.
Details
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Theoretically, the caffeine in yerba mate might increase the risk of hypokalemia when used concomitantly with other diuretics.
Details
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Theoretically, the caffeine in yerba mate might increase the risk for stimulant adverse effects when used concomitantly with ephedrine.
Details
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 the caffeine in yerba mate.
Details
Yerba mate contains caffeine. Estrogen inhibits caffeine metabolism (2714).
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Theoretically, the caffeine in yerba mate might reduce the effects of ethosuximide and increase the risk for convulsion.
Details
Yerba mate contains caffeine. Animal research shows 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, the caffeine in yerba mate might reduce the effects of felbamate and increase the risk for convulsion.
Details
Yerba mate contains caffeine. Animal research shows 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 the caffeine in yerba mate.
Details
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Theoretically, the caffeine in yerba mate might increase the levels and adverse effects of flutamide.
Details
Yerba mate contains caffeine. 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 the caffeine in yerba mate.
Details
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Theoretically, abrupt withdrawal of the caffeine in yerba mate might increase serum lithium levels.
Details
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Theoretically, metformin might increase the levels and adverse effects of the caffeine in yerba mate.
Details
Yerba mate contains caffeine. 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 the caffeine in yerba mate.
Details
Yerba mate contains caffeine. Methoxsalen reduces caffeine metabolism (23572).
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Theoretically, mexiletine might increase the levels and adverse effects of the caffeine in yerba mate.
Details
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Theoretically, use of yerba mate with midazolam might increase midazolam metabolite levels and adverse effects.
Details
In vitro research shows that yerba mate extract containing 6.75% chlorogenic acid significantly inhibits the metabolism of midazolam via inhibition of cytochrome P450 3A4 (CYP3A4)(105811).
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Theoretically, the caffeine in yerba mate might increase risk of a hypertensive crisis when used concomitantly with MAOIs.
Details
Yerba mate contains caffeine. 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, the caffeine in yerba mate might increase risk of hypertension when used concomitantly with nicotine.
Details
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Theoretically, the caffeine in yerba mate might decrease the effects of pentobarbital.
Details
The caffeine in yerba mate might negate the hypnotic effects of pentobarbital (13742).
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Theoretically, the caffeine in yerba mate might reduce the effects of phenobarbital and increase the risk for convulsions.
Details
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Theoretically, phenylpropanolamine might increase the risk of hypertension as well as the levels and adverse effects of the caffeine in yerba mate.
Details
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Theoretically, the caffeine in yerba mate might reduce the effects of phenytoin and increase the risk for convulsions.
Details
Yerba mate contains caffeine. Animal research suggests that caffeine can decrease the anticonvulsant activity of phenytoin (23561). The effect does not seem to be related to the seizure threshold-lowering effects of caffeine. However, the exact mechanism of this interaction is unclear.
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Theoretically, the caffeine in yerba mate might increase the levels and clinical effects of pioglitazone.
Details
Yerba mate 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 the caffeine in yerba mate.
Details
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Theoretically, concomitant use of riluzole and yerba mate might increase levels and adverse effects of both riluzole and the caffeine in yerba mate.
Details
Yerba mate contains caffeine. 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 of stimulant drugs and yerba mate might increase stimulant adverse effects.
Details
Yerba mate contains caffeine. Due to the CNS stimulant effects of the caffeine, concomitant use can increase the risk of adverse effects (11832).
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Theoretically, terbinafine might increase the levels and adverse effects of the caffeine in yerba mate.
Details
Yerba mate contains caffeine. Terbinafine decreases the rate of caffeine clearance by 19% (11740).
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Theoretically, the caffeine in yerba mate might increase the levels and adverse effects of theophylline.
Details
Yerba mate contains caffeine. Caffeine decreases theophylline clearance by 23% to 29% (11741).
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Theoretically, the caffeine in yerba mate might increase the levels and adverse effects of tiagabine.
Details
Yerba mate contains caffeine. 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 the caffeine in yerba mate.
Details
Yerba mate contains caffeine. In vitro research shows that ticlopidine can inhibit caffeine metabolism (23557). However, this effect has not been reported in humans.
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Theoretically, the caffeine in yerba mate might reduce the effects of valproate and increase the risk for convulsions.
Details
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Theoretically, verapamil might increase the levels and adverse effects of the caffeine in yerba mate.
Details
Yerba mate contains caffeine. Verapamil increases plasma caffeine concentrations by 25% (11741).
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Below is general information about the adverse effects of the known ingredients contained in the product Mu Zest Tea. 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, black tea is well tolerated when consumed as a beverage in moderate amounts.
Most Common Adverse Effects:
Orally: Many of the adverse effects of black tea can be attributed to its caffeine content, such as diuresis, gastric irritation, insomnia, nausea, nervousness, restlessness, tachycardia, tachypnea, tremors, and vomiting.
Serious Adverse Effects (Rare):
Orally: Many of the adverse effects of black tea can be attributed to its caffeine content, such as arrhythmia, chest pain, convulsions, delirium, premature heartbeat, and respiratory alkalosis. Large doses of caffeine can cause massive catecholamine release and subsequent sinus tachycardia, metabolic acidosis, hyperglycemia, and ketosis.
Cardiovascular
...Orally, black tea can cause some cardiovascular-related adverse events.
Some of these effects may be due to the caffeine content of black tea. Acute administration of black tea can cause increased blood pressure. However, regular consumption does not seem to increase blood pressure or pulse, even in patients with mild hypertension (1451,1452,2722). Also, epidemiological research suggests that there is no association of caffeine consumption with incidence of hypertension (13739).
Black tea, which contains caffeine, may cause other adverse cardiovascular effects when used orally. These effects include tachycardia, tachypnea, chest pain, premature heartbeat, arrhythmia, and hypertension (2729,11832,11838,13735). Large doses of caffeine can also cause massive catecholamine release and subsequent sinus tachycardia (13734).
There is evidence that daily consumption of strong black tea (2 liters) or black tea solids (4 grams) can raise plasma homocysteine levels. It is unclear if lower doses have this effect (8035). Some epidemiological research has linked tea consumption with ischemic heart disease and total mortality (220,36339). Combining caffeinated beverages such as black tea with ephedra may theoretically increase the risk of adverse cardiovascular events. There is a report of ischemic stroke in an athlete who consumed ephedra 40-60 mg, creatine monohydrate 6 grams, caffeine 400-600 mg, and a variety of other supplements daily for 6 weeks (1275).
Dental ...Orally, black tea may cause tooth surface loss and teeth staining (36370).
Endocrine
...Black tea contains caffeine.
Large doses of caffeine can cause massive catecholamine release and subsequent metabolic acidosis, hyperglycemia, and ketosis (13734).
Some evidence shows caffeine is associated with fibrocystic breast disease, breast cancer, and endometriosis. However, other research has not supported this finding (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 found no association between consumption of caffeine-containing beverages such as black tea and the incidence of invasive breast cancer in models adjusted for demographic, lifestyle, and reproductive factors (108806). Also, a dose-response analysis of two low-quality observational studies found that high consumption of caffeine is not associated with an increased risk of breast cancer (108807).
Gastrointestinal ...Orally, caffeine in black tea can cause gastric irritation, nausea, and vomiting (11832,11838,13735). Some believe that long-term use of caffeine can cause withdrawal symptoms following discontinuation of use. However, the existence of caffeine withdrawal is controversial. Some researchers think that if it exists, it appears to be of little clinical significance (11839). Gastrointestinal withdrawal symptoms such as nausea and vomiting have been described. However, these symptoms may be from nonpharmacological factors related to knowledge and expectation of effects. Clinically significant gastrointestinal symptoms caused by caffeine withdrawal may be uncommon (2723,11839).
Hematologic ...Orally, caffeine in black tea can cause hypokalemia (11832,11838,13735). In infants, black tea can cause microcytic anemia (631).
Immunologic ...Orally, caffeine in black tea can cause anaphylaxis in sensitive individuals, although true IgE-mediated caffeine allergy seems to be relatively rare (11315).
Musculoskeletal
...Some epidemiological research suggests that caffeine, which is found in black tea, may be associated with an increased risk of osteoporosis, but conflicting evidence exists.
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 for 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).
Some researchers believe that stopping regular use of caffeine may cause withdrawal symptoms such as muscle tension and muscle pains. However, these symptoms may be from nonpharmacological factors related to knowledge and expectation of effects (2723,11839).
Neurologic/CNS
...Orally, caffeine in black tea can cause insomnia, nervousness, headache, anxiety, agitation, jitteriness, restlessness, ringing in the ears, tremors, delirium, and convulsions (11832,11838,13735).
Caffeine may also exacerbate sleep disturbances in patients with acquired immunodeficiency syndrome (AIDS) (10204).
There is some concern that stopping regular use of caffeine may cause withdrawal symptoms such as headache; tiredness and fatigue; decreased energy, alertness, and attentiveness; drowsiness; decreased contentedness; depressed mood; difficulty concentrating; irritability; and lack of clear-headedness are typical of caffeine withdrawal (13738). Other symptoms such as delirium, nervousness, restlessness, and anxiety have been described. However, these symptoms may be from nonpharmacological factors related to knowledge and expectation of effects (2723,11839).
Oncologic ...There is some evidence that consumption of black tea (greater than 1 cup per day) may increase the risk of colon and rectal cancers (8041,36482). Drinking 3 or more cups daily has been shown to increase the risk of pancreatic cancer (36507). In addition, drinking black tea more than once a day, drinking strong black tea, or using more than 300 grams of tea leaves per month is associated with an approximately 2-fold increased risk of esophageal cancer when compared with drinking black tea up to once daily, drinking mild to moderate black tea, or using up to 300 grams of tea leaves per month (102756). Some evidence also shows caffeine, which is found in black tea, is associated with breast cancer in females. However, this is controversial since findings are conflicting (8043).
Pulmonary/Respiratory ...Orally, caffeine in black tea may cause tachypnea-induced respiratory alkalosis (11832,11838,13735). Some researchers think that stopping regular use of caffeine may cause withdrawal symptoms such as runny nose. However, this symptom may be from nonpharmacological factors related to knowledge and expectation of effects (2723,11839).
Renal ...Orally, caffeine in black tea may cause diuresis (11832,11838,13735).
General
...Orally, carob seems to be generally well tolerated when eaten as food or when added to food.
Serious Adverse Effects (Rare):
Orally: Serious allergic reactions in sensitive individuals.
Gastrointestinal ...Orally, the addition of a carob milk thickener (Carobel) to preterm infant feeds has been associated with necrotizing enterocolitis leading to death in two low birth-weight infants (39991). This adverse effect has not been reported in term infants.
Immunologic
...A five month-old child who was allergic to an anti-regurgitation milk formula containing carob gum experienced urticaria, rash, and explosive vomiting within 30 minutes of administration of the formula (39969).
In a separate case, an 11-week-old infant with Down syndrome presented with persistent vomiting, watery diarrhea, and lethargy requiring IV hydration. The infant had previously been diagnosed with food protein-induced enterocolitis syndrome (FPIES), likely due to cow's milk. He had consumed formula containing a carob gum thickener; the reaction resolved upon discontinuation of the carob gum additive. An oral challenge test to carob produced a reaction, confirming this as the likely causative agent (104235). In another case, a 52-year-old man experienced chest tightness, throat discomfort, and burning sensations related to an oral allergy to carob pods (97850).
Occupational exposure to carob flour has been reported to cause allergic asthma and rhinitis (39987,40015).
General
...Orally, chicory seems to be well tolerated.
Most Common Adverse Effects:
Orally: Abdominal pain, belching, bloating, and flatulence.
Dermatologic ...Occupational exposure to chicory may cause skin rash, contact dermatitis, or generalized pruritus (41609,93649). The sesquiterpene lactones of the plant may be the allergens (41609). Chicory may cause an allergic reaction in individuals sensitive to the Asterceae/Compositae family (25416). Members of this family include ragweed, chrysanthemums, marigolds, daisies, and many other herbs.
Gastrointestinal ...Orally, fructo-oligosaccharides, such as those extracted from chicory, can cause flatulence, belching, abdominal pains, intestinal sounds and bloating, which occur commonly, but are mild at doses of 10 grams daily (740,745,750,8509,93716).
Immunologic ...Occupational exposure to chicory may cause allergic reactions. Dyspnea and anaphylaxis have also been reported in a patient with regular occupational exposure to chicory. This patient also experienced contact dermatitis and generalized pruritus (93649).
Pulmonary/Respiratory ...Occupational exposure to chicory may cause asthma and rhinoconjunctivitis (41617,93648). Dyspnea and anaphylaxis have also been reported in a patient with regular occupational exposure to chicory. This patient also experienced contact dermatitis and generalized pruritus (93649).
General
...Orally, dandelion seems to be well tolerated.
Most Common Adverse Effects:
Orally: Diarrhea, heartburn, and stomach discomfort.
Topically: Dermatitis in sensitive individuals.
Serious Adverse Effects (Rare):
Orally: Anaphylaxis in sensitive individuals.
Cardiovascular ...In one report, a 39-year-old obese woman developed palpitations and syncope after taking a weight loss supplement containing a combination of dandelion, bladderwrack, and boldo for 3 weeks. The patient was found to have prolonged QT-interval on ECG and frequent episodes of sustained polymorphic ventricular tachycardia (14321). It is not clear whether dandelion, another ingredient, or the combination of ingredients is responsible for this adverse effect. The product was not analyzed to determine the presence of any potential toxic contaminants.
Dermatologic ...Topically, dandelion can cause contact dermatitis and erythema multiforme in sensitive individuals. Dandelion can cause an allergic reaction in individuals sensitive to the Asteraceae/Compositae family (13478,13481,42893,46945,46977). Members of this family include ragweed, chrysanthemums, marigolds, daisies, and many other herbs.
Endocrine ...In one report, a 56-year-old man with renal impairment developed hyperoxalaemia and peripheral gangrene after ingesting large amounts of dandelion tea (10 to 15 cups daily for 6 months). The adverse effect was attributed to the high oxalate content of dandelion tea (258 mcmol/L) and reduced renal oxalate clearance caused by renal impairment (90639). In another report, a 58-year-old woman with type 2 diabetes who was being treated with insulin developed hypoglycemic symptoms 2 weeks after beginning to eat salads containing dandelion (46960). The hypoglycemic effect was attributed to the potential alpha-glucosidase inhibitory activity of dandelion.
Gastrointestinal ...Gastrointestinal symptoms, including stomach discomfort, diarrhea, and heartburn, have been reported following oral use of dandelion (19146,36931). A case of intestinal blockage has been reported for a patient who ingested a large amount of dandelion greens three weeks after undergoing a stomach operation (46981). Also, a case of hemorrhagic cystitis has been reported for a 33-year-old woman who took a specific herbal product (Slim-Kombu, Balestra and Mech, Vicenza, Italy) containing 20 herbal extracts, including dandelion extract. Symptoms resolved after the patient discontinued using the product, and symptoms resumed when the patient began taking the supplement again four months later. While various ingredients in the supplement may have contributed to the symptoms, it is possible that dandelion extract may have contributed to the effect due to its diuretic, laxative, cholagogue, and antirheumatic properties (46959).
Other ...Orally, products containing dandelion pollen can cause allergic reactions, including anaphylaxis (13479,13480). Also, rhinoconjunctivitis and asthma have been reported after handling products such as bird feed containing dandelion and other herbs, with reported positive skin tests for dandelion hypersensitivity (46948). Dandelion pollen may cause pollinosis, such as allergic rhinitis and conjunctivitis (18065,46951,46964,46966,46972).
General
...Orally, licorice is generally well tolerated when used in amounts commonly found in foods.
It seems to be well tolerated when licorice products that do not contain glycyrrhizin (deglycyrrhizinated licorice) are used orally and appropriately for medicinal purposes or when used topically, short-term.
Most Common Adverse Effects:
Orally: Headache, nausea, and vomiting.
Topically: Contact dermatitis.
Intravenously: Diarrhea, itching, nausea, and rash.
Serious Adverse Effects (Rare):
Orally: Case reports have raised concerns about acute renal failure, cardiac arrest, cardiac arrhythmias, hypertension, hypokalemia, muscle weakness, paralysis, pseudohyperaldosteronism, and seizure associated with long-term use or large amounts of licorice containing glycyrrhizin.
Cardiovascular
...Orally, excessive licorice ingestion can lead to pseudohyperaldosteronism, which can precipitate cardiovascular complications such as hypertension and hypertensive crisis, ventricular fibrillation or tachycardia, sinus pause, and cardiac arrest.
These effects are due to the licorice constituent glycyrrhizin and usually occur when 20-30 grams or more of licorice product is consumed daily for several weeks (781,15590,15592,15594,15596,15597,15599,15600,16835,97213) (104563,108574,108576,110305,112234). In one case report, an 89-year-old female taking an herbal medicine containing licorice experienced a fatal arrhythmia secondary to licorice-induced hypokalemia. The patient presented to the hospital with recurrent syncope, weakness, and fatigue for 5 days after taking an herbal medicine containing licorice for 2 months. Upon admission to the hospital, the patient developed seizures, QT prolongation, and ventricular arrhythmia requiring multiple defibrillations. Laboratory tests confirmed hypokalemia and pseudohyperaldosteronism (112234).
However, people with cardiovascular or kidney conditions may be more sensitive, so these adverse events may occur with doses as low as 5 grams of licorice product or glycyrrhizin 100 mg daily (15589,15593,15598,15600,59726). A case report in a 54-year-old male suggests that malnutrition might increase the risk of severe adverse effects with excessive licorice consumption. This patient presented to the emergency room with cardiac arrest and ventricular fibrillation after excessive daily consumption of licorice for about 3 weeks. This caused pseudohyperaldosteronism and then hypokalemia, leading to cardiovascular manifestations. In spite of resuscitative treatment, the patient progressed to kidney failure, refused dialysis, and died shortly thereafter (103791).
Dermatologic
...There have been reports of contact allergy, resulting in an itchy reddish eruption, occurring in patients that applied cosmetic products containing oil-soluble licorice extracts (59912).
There have also been at least 3 cases of allergic contact dermatitis reported with the topical application of glycyrrhizin-containing products to damaged skin. In one case report, a 31-year-old female with acne presented with a 2-year history of pruritic erythematous-scaly plaques located predominantly on the face and neck after the use of a cosmetic product containing licorice root extract 1%. The patient had a positive skin patch test to licorice root extract, leading the clinicians to hypothesize that the use of benzoyl peroxide, a strong irritant, might have sensitized the patient to licorice (108578). Burning sensation, itching, redness, and scaling were reported rarely in patients applying a combination of licorice, calendula, and snail secretion filtrate to the face. The specific role of licorice is unclear (110322).
In rare cases, the glycyrrhizin constituent of licorice has caused rash and itching when administered intravenously (59712).
Endocrine
...Orally, excessive licorice ingestion can cause a syndrome of apparent mineralocorticoid excess, or pseudohyperaldosteronism, with sodium and water retention, increased urinary potassium loss, hypokalemia, and metabolic alkalosis due to its glycyrrhizin content (781,10619,15591,15592,15593,15594,15595,15596,15597,15598)(15600,16057,16835,25659,25660,25673,25719,26439,59818,59822)(59832,59864,91722,104563,108568,108574,110305,112234).
These metabolic abnormalities can lead to hypertension, edema, EKG changes, fatigue, syncope, arrhythmias, cardiac arrest, headache, lethargy, muscle weakness, dropped head syndrome (DHS), rhabdomyolysis, myoglobinuria, paralysis, encephalopathy, respiratory impairment, hyperparathyroidism, and acute kidney failure (10393,10619,15589,15590,15593,15594,15596,15597,15599)(15600,16057,16835,25660,25673,25719,26439,31562,59709,59716)(59720,59740,59787,59820,59826,59882,59889,59900,91722,97214,100522) (104563,108576,108577). These effects are most likely to occur when 20-30 grams of licorice products containing glycyrrhizin 400 mg or more is consumed daily for several weeks (781,15590,15592,15594,15596,15597,15599,15600,16835,108574). However, some people may be more sensitive, especially those with hypertension, diabetes, heart problems, or kidney problems (15589,15593,15598,15600,59726,108576,108577) and even low or moderate consumption of licorice may cause hypertensive crisis or hypertension in normotensive individuals (1372,97213). The use of certain medications with licorice may also increase the risk of these adverse effects (108568,108577). One case report determined that the use of large doses of licorice in an elderly female stabilized on fludrocortisone precipitated hypokalemia and hypertension, requiring inpatient treatment (108568). Another case report describes severe hypokalemia necessitating intensive care treatment due to co-ingestion of an oral glycyrrhizin-specific product and hydrochlorothiazide for 1 month (108577). Glycyrrhetinic acid has a long half-life, a large volume of distribution, and extensive enterohepatic recirculation. Therefore, it may take 1-2 weeks before hypokalemia resolves (781,15595,15596,15597,15600). Normalization of the renin-aldosterone axis and blood pressure can take up to several months (781,15595,108568). Treatment typically includes the discontinuation of licorice, oral and intravenous potassium supplementation, and short-term use of aldosterone antagonists, such as spironolactone (108574,108577).
Chewing tobacco flavored with licorice has also been associated with toxicity. Chewing licorice-flavored tobacco, drinking licorice tea, or ingesting large amounts of black licorice flavored jelly beans or lozenges has been associated with hypertension and suppressed renin and aldosterone levels (12671,12837,97214,97215,97217,108574). One case report suggests that taking a combination product containing about 100 mg of licorice and other ingredients (Jintan, Morishita Jintan Co.) for many decades may be associated with hypoaldosteronism, even up to 5 months after discontinuation of the product (100522). In another case report, licorice ingestion led to hyperprolactinemia in a female (59901). Licorice-associated hypercalcemia has also been noted in a case report (59766).
Gastrointestinal ...Nausea and vomiting have been reported rarely following oral use of deglycyrrhizinated licorice (25694,59871). Intravenously, the glycyrrhizin constituent of licorice has rarely caused gastric discomfort, diarrhea, or nausea (59712,59915).
Immunologic ...There have been reports of contact allergy, resulting in an itchy reddish eruption, occurring in patients that applied cosmetic products containing oil-soluble licorice extracts (59912). There have also been at least 3 cases of allergic contact dermatitis reported with the topical application of glycyrrhizin-containing products to damaged skin. In one case report, a 31-year-old female with acne presented with a 2-year history of pruritic erythematous-scaly plaques located predominantly on the face and neck after the use of a cosmetic product containing licorice root extract 1%. The patient had a positive skin patch test to licorice root extract, leading the clinicians to hypothesize that the use of benzoyl peroxide, a strong irritant, might have sensitized the patient to licorice (108578).
Musculoskeletal ...In a case report, excessive glycyrrhizin-containing licorice consumption led to water retention and was thought to trigger neuropathy and carpal tunnel syndrome (59791).
Neurologic/CNS ...Orally, licorice containing larger amounts of glycyrrhizin may cause headaches. A healthy woman taking glycyrrhizin 380 mg daily for 2 weeks experienced a headache (59892). Intravenously, the glycyrrhizin constituent of licorice has rarely caused headaches or fatigue (59721). In a case report, licorice candy ingestion was associated with posterior reversible encephalopathy syndrome accompanied by a tonic-clonic seizure (97218).
Ocular/Otic ...Orally, consuming glycyrrhizin-containing licorice 114-909 grams has been associated with transient visual loss (59714).
Pulmonary/Respiratory ...Orally, large amounts of licorice might lead to pulmonary edema. In one case report, a 64-year old male consumed 1020 grams of black licorice (Hershey Twizzlers) containing glycyrrhizin 3.6 grams over 3 days, which resulted in pulmonary edema secondary to pseudohyperaldosteronism (31561). Intravenously, the glycyrrhizin constituent of licorice has caused cold or flu-like symptoms, although these events are not common (59712,59721).
General ...Orally, sarsaparilla seems to be well tolerated.
Gastrointestinal ...Orally, there is some concern that sarsaparilla may cause GI irritation when used in large amounts (11,18). However, these claims cannot be substantiated.
Pulmonary/Respiratory ...Occupational exposure to sarsaparilla root dust can cause rhinitis and asthma symptoms (4111).
Renal ...Orally, there is some concern that sarsaparilla may cause temporary kidney impairment and diuresis, possibly leading to shock, when used in large amounts (11,18). However, these claims cannot be substantiated.
General
...When used orally in high doses or long-term, yerba mate may be unsafe.
Most Common Adverse Effects:
Orally: Many of the adverse effects of yerba mate can be attributed to its caffeine content, such as diuresis, gastric irritation, insomnia, nausea, nervousness, restlessness, tachycardia, tachypnea, and tremors.
Serious Adverse Effects (Rare):
Orally: Cancer, hyperglycemia, ketosis, metabolic acidosis, sinus tachycardia. These adverse effects are more common with high doses or long-term use.
Cardiovascular
...Orally, yerba mate may cause cardiovascular-related adverse effects due to its caffeine content.
High doses of mate providing 250 mg of caffeine can increase blood pressure. However, this doesn't seem to occur in people who habitually consume caffeine products (2722). Also, epidemiological research suggests that there is no association of caffeine consumption with incidence of hypertension (13739).
Due to its caffeine content, yerba mate may cause other adverse cardiovascular effects when used orally. These effects include tachycardia, quickened respiration, chest pain, premature heartbeat, arrhythmia, and hypertension (11832,11838,13735). Large doses of caffeine can also cause massive catecholamine release and subsequent sinus tachycardia (13734). There is also one report of venous occlusive disease associated with excessive, long-term mate consumption (5614).
Epidemiological research has found that regular caffeine intake of up to 400 mg per day, or approximately 8-10 cups of yerba mate, is not associated with an increased incidence of atrial fibrillation (38018,38076,91028,91034,97451,97453), atherosclerosis (38033), cardiac ectopy (91127), stroke (37804), ventricular arrhythmia (95948,97453), and cardiovascular disease in general (37805,98806).
Combining caffeine beverages such as yerba mate with ephedra may theoretically increase the risk of adverse cardiovascular events. There is one report of ischemic stroke in an athlete who consumed ephedra 40-60 mg, creatine monohydrate 6 grams, caffeine 400-600 mg, and a variety of other supplements daily for six weeks (1275).
Endocrine ...Yerba mate contains caffeine. Orally, large doses of caffeine can cause massive catecholamine release and subsequent metabolic acidosis, hyperglycemia, and ketosis (13734). Some evidence shows caffeine 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).
Gastrointestinal ...Orally, drinking yerba mate infusions has been associated with nausea and irritation of the stomach or oral mucosa in a small number of patients in one clinical study (86657). Yerba mate contains caffeine. Orally, caffeine can cause gastric irritation, nausea, and vomiting (11832,11838,13735). Caffeine-containing beverages can stimulate gastric secretion in humans, which may potentiate ulcer symptoms (36404). Some believe that long-term use of caffeine can cause withdrawal symptoms following discontinuation of use. However, the existence of caffeine withdrawal is controversial. Some researchers think that if it exists, it appears to be of little clinical significance (2723,11839). Gastrointestinal withdrawal symptoms such as nausea and vomiting have been described. However, these symptoms may be from nonpharmacological factors related to knowledge and expectation of effects. Clinically significant gastrointestinal symptoms caused by caffeine withdrawal may be uncommon (2723,11839).
Hematologic ...Yerba mate contains caffeine. Orally, caffeine can cause hypokalemia (11832,11838,13735).
Immunologic ...Yerba mate contains caffeine. Orally, caffeine can cause anaphylaxis in sensitive individuals, although true IgE-mediated caffeine allergy seems to be relatively rare (11315).
Musculoskeletal
...Yerba mate contains caffeine.
Some epidemiological research suggests that caffeine may be associated with an increased risk of osteoporosis, but conflicting evidence exists. 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 for the detrimental effect of caffeine on bone mass (2669). However, moderate caffeine intake of less than 400 mg per day, or approximately 8-10 cups of yerba mate, does not seem to significantly increase osteoporosis risk in most postmenopausal adults with normal calcium intake (2669,6025,10202,11317,98806).
Some researchers believe that stopping regular use of caffeine may cause withdrawal symptoms such as muscle tension and muscle pains. However, these symptoms may be from nonpharmacological factors related to knowledge and expectation of effects (2723,11839). However, there is a case of withdrawal in a premature neonate following chronic parental drinking of yerba mate (86618). Symptoms included hypertonia in the limbs and brisk tendon reflexes. The authors indicated that high concentrations of caffeine and theobromine were found in the placenta, cord serum, neonatal urine, parental and neonatal hair, meconium, and breast milk. Although symptoms progressively disappeared at 84 hours of age, irritability was still occasionally present at discharge (24 days of age).
Neurologic/CNS
...Orally, drinking yerba mate infusions has been associated with insomnia in a small number of patients in one clinical study (86657).
Yerba mate contains caffeine. Orally, caffeine can cause insomnia, nervousness, headache, anxiety, agitation, jitteriness, restlessness, ringing in the ears, tremors, delirium, and convulsions (11832,11838,13735). Caffeine may also exacerbate sleep disturbances in patients with acquired immunodeficiency syndrome (AIDS) (10204).
There is some concern that stopping regular use of caffeine may cause withdrawal symptoms such as headache, tiredness and fatigue, decreased energy, alertness, and attentiveness, drowsiness, decreased contentedness, depressed mood, difficulty concentrating, irritability, and lack of clear-headedness are typical of caffeine withdrawal (13738). Other symptoms such as delirium, nervousness, restlessness, and anxiety have been described. However, these symptoms may be from nonpharmacological factors related to knowledge and expectation of effects (2723,11839). However, there is a case of withdrawal in a premature neonate following chronic parental drinking of yerba mate (86618). Symptoms included jitteriness and irritability and a high-pitched cry. The authors indicated that high concentrations of caffeine and theobromine were found in the placenta, cord serum, neonatal urine, parental and neonatal hair, meconium, and breast milk. Although symptoms progressively disappeared at 84 hours of age, irritability was still occasionally present at discharge (24 days of age).
Oncologic ...Orally, the prolonged use of yerba mate or use of yerba mate in high doses (typically more than 1-2 liters daily) is associated with an increased risk of cancer, including mouth, esophageal, laryngeal, kidney, bladder, cervical, prostate, and lung cancer (1528,1529,1530,1531,11863,11864,92150,86595,86614,86700,86701). The effect seems to be cumulative and dose dependent. The risk of cancer with yerba mate use seems to increase if it is taken as a warm beverage. In 1991, the International Agency for Research on Cancer (IARC), reported that hot yerba mate drinking is a 2A agent, meaning it is probably carcinogenic for humans (92150). A statement published in 2016 stated there is no conclusive evidence for carcinogenicity when yerba mate is consumed at temperatures that are "not very hot" (95015). Drinking very hot beverages is believed to be a probable cause of esophageal cancer in humans (95015). Concomitant tobacco and alcohol use can increase risk 7-fold (11863).
Pulmonary/Respiratory ...Yerba mate contains caffeine. Orally, caffeine may cause tachypnea-induced respiratory alkalosis (11832,11838,13735). Some researchers think that stopping regular use of caffeine may cause withdrawal symptoms such as runny nose. However, this symptom may be from nonpharmacological factors related to knowledge and expectation of effects (2723,11839).
Renal ...Yerba mate contains caffeine. Orally, caffeine may cause diuresis (11832,11838,13735).
