Ingredients | Amount Per Serving |
---|---|
(Ascorbic Acid)
|
100 mg |
(root)
(from Polygonum cuspidatum)
(Resveratrol (Form: from Polygonum cuspidatum (Alt. Name: Tiger Cane) PlantPart: root Genus: Polygonum Species: cuspidatum) PlantPart: root )
|
20 mg |
<=18 mg | |
Green Tea 5:1 extract
(Camellia sinensis )
(leaf)
(50% Polyphenolics)
(Green Tea 5:1 extract (Form: 50% Polyphenolics) PlantPart: leaf Genus: Camellia Species: sinensis )
|
200 mg |
100 mg | |
(Ancellota lambrusco )
(25% Polyphenols)
(Grape Skin Extract (Form: 25% polyphenols) Genus: Ancellota Species: lambrusco )
|
100 mg |
(Vitis vinifera )
(seed)
(95% Polyphenols)
(Grape seed extract (Form: 95% Polyphenols) PlantPart: seed Genus: Vitis Species: vinifera )
|
50 mg |
Trans-Pterostilbene
(pTeroPure)
|
5 mg |
Cellulose, Calcium Phosphate (Alt. Name: Ca Phosphate), Stearic Acid (Alt. Name: C18:0), Magnesium Stearate Note: vegetable source, Silicon Dioxide (Alt. Name: SiO2), Food Grade Coating
Below is general information about the effectiveness of the known ingredients contained in the product Resveratrol Synergy. 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
Below is general information about the safety of the known ingredients contained in the product Resveratrol Synergy. 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 used orally in amounts commonly found in foods. Grapes and grape skin extracts have Generally Recognized As Safe (GRAS) status for use in foods in the US (4912).
POSSIBLY SAFE ...when the whole fruit of the grape, or extracts of the fruit, seed, or leaf, are used orally and appropriately in medicinal amounts. Grape seed extracts have been used with apparent safety in doses up to 200 mg daily for up to 11 months (9182,53016) and in doses up to 2000 mg daily for up to 3 months (53149,53190). Specific grape fruit extracts (Stilvid, Actafarma; Cognigrape, Bionap srl) have been used with apparent safety in doses up to 250-350 mg daily for 3-12 months or 700 mg daily for 6 months (53254,53256,96198). A specific grape leaf extract (AS 195, Antistax, Boehringer Ingelheim) has been used with apparent safety in doses up to 720 mg daily for up to 3 months (2538,52985,53005,53206). A preparation of dehydrated whole grapes, equivalent to 250 grams of fresh grapes daily, has also been used with apparent safety for up to 30 days (18228). A specific grape seed extract (Enovita; Indena SpA) 150 mg twice daily, standardized to provide at least 95% oligomeric proanthocyanins, has been used with apparent safety for up to 16 weeks (108091) ...when used topically and appropriately. Creams and ointments containing grape seed extract 2% or 5% have been used topically with apparent safety for up to 3 weeks (91539,100955). There is insufficient reliable information available about the safety of other grape plant parts when used topically.
CHILDREN: LIKELY SAFE
when used orally in amounts commonly found in foods.
Grapes and grape skin extracts have Generally Recognized As Safe (GRAS) status for use in foods in the US (4912). However, whole grapes should be eaten with caution in children aged 5 years and under. Whole grapes can be a choking hazard for young children (96193). To reduce the risk of choking, whole grapes should be cut in half or quartered before being given to children. There is insufficient reliable information available about the safety of grape when used in medicinal amounts in children.
PREGNANCY AND LACTATION: LIKELY SAFE
when used orally in amounts commonly found in foods.
There is insufficient reliable information available about the safety of medicinal amounts during pregnancy and breast-feeding; avoid using in amounts greater than what is commonly found in foods.
POSSIBLY SAFE ...when used orally and appropriately, short-term. Quercetin has been used with apparent safety in doses up to 1 gram daily for up to 12 weeks (481,1998,1999,16418,16429,16430,16431,96774,96775,96782)(99237,102539,102540,102541,104229,104679,106498,106499,107450,109620)(109621). ...when used intravenously and appropriately. Quercetin has been used with apparent safety in doses less than 945 mg/m2. Higher doses have been reported to cause nephrotoxicity (9564,16418). There is insufficient reliable information available about the safety of quercetin when used topically.
POSSIBLY UNSAFE ...when used intravenously in large amounts. Doses greater than 945 mg/m2 have been reported to cause nephrotoxicity (9564,16418).
PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.
LIKELY SAFE ...when used in amounts found in foods (2030).
POSSIBLY SAFE ...when taken orally in doses of up to 1500 mg daily for up to 3 months (71066,71097,91328,91331,95825,95833,98910,100695,105183,109163,109167). Higher doses of 2000-3000 mg daily have been well tolerated when taken for 2-6 months, but are more likely to cause gastrointestinal side effects (91327,98908). ...when used topically for up to 30 days (71064). ...when used as an intranasal spray for up to 4 weeks (97339).
CHILDREN: LIKELY SAFE
when used in amounts found in foods.
CHILDREN: POSSIBLY SAFE
when used as an intranasal spray for up to 2 months in children 4 years of age and older (91332).
There is insufficient reliable information available about the safety of resveratrol when used by mouth in larger amounts as medicine.
PREGNANCY AND LACTATION: LIKELY SAFE
when used in amounts found in foods (2030).
Resveratrol is found in grape skins, grape juice, wine, and other food sources. However, wine should not be used as a source of resveratrol during pregnancy and lactation.
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 Resveratrol Synergy. 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, grape extracts may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
|
Ingesting grape juice with cyclosporine can reduce cyclosporine absorption.
A small pharmacokinetic study in healthy young adults shows that intake of purple grape juice 200 mL along with cyclosporine can decrease the absorption of cyclosporine by up to 30% when compared with water (53177). Separate doses of grape juice and cyclosporine by at least 2 hours to avoid this interaction.
|
Theoretically, grape juice might reduce the levels of CYP1A2 substrates.
A small pharmacokinetic study in healthy adults shows that ingestion of 200 mL of grape juice decreases phenacetin plasma levels. This is thought to be due to induction of CYP1A2 (2539).
|
It is unclear if grape juice or grape seed extract inhibits CYP2C9; research is conflicting.
In vitro evidence shows that grape seed extract or grape juice might inhibit CYP2C9 enzymes (11094,53011,53089). However, a small pharmacokinetic study in healthy adults shows that drinking 8 ounces of grape juice once does not affect the clearance of flurbiprofen, a probe-drug for CYP2C9 metabolism (11094). The effects of continued grape juice consumption are unclear.
|
Theoretically, grape seed extract may increase the levels of CYP2D6 substrates.
In vitro evidence suggests that grape seed extract might inhibit CYP2D6 enzymes (53011). However, this interaction has not been reported in humans.
|
Theoretically, grape seed extract might increase the levels of CYP2E1 substrates.
In vitro and animal research suggests that grape seed proanthocyanidin extract inhibits CYP2E1 enzymes (52949). However, this interaction has not been reported in humans.
|
It is unclear if grape seed extract inhibits or induces CYP3A4; research is conflicting.
|
Theoretically, long-term intake of grape seed extract might decrease the effects of midazolam.
Animal research shows that subchronic ingestions of grape seed extract can increase the elimination of intravenous midazolam by increasing hepatic CYP3A4 activity. Single doses of grape seed extract do not appear to affect midazolam elimination (53011).
|
Grape juice might decrease phenacetin absorption.
A small pharmacokinetic study in healthy adults shows that ingestion of 200 mL of grape juice decreases phenacetin plasma levels. This is thought to be due to induction of cytochrome P450 1A2 (CYP1A2) (2539).
|
Theoretically, concomitant use of quercetin and antidiabetes drugs might increase the risk of hypoglycemia.
Clinical research suggests that a combination of quercetin, myricetin, and chlorogenic acid reduce levels of fasting glucose in patients with type 2 diabetes, including those already taking antidiabetes agents (96779). The effect of quercetin alone is unknown. |
Theoretically, taking quercetin with antihypertensive drugs might increase the risk of hypotension.
|
Theoretically, concomitant use might increase the levels and adverse effects of cyclosporine.
A small study in healthy volunteers shows that pretreatment with quercetin increases plasma levels and prolongs the half-life of a single dose of cyclosporine, possibly due to inhibition of p-glycoprotein or cytochrome P450 3A4 (CYP3A4), which metabolizes cyclosporin (16434). |
Theoretically, concomitant use might increase the levels and adverse effects of CYP2C8 substrates.
|
Theoretically, concomitant use might increase the levels and adverse effects of CYP2C9 substrates.
A small clinical study in healthy volunteers shows that taking quercetin 500 mg twice daily for 10 days prior to taking diclofenac, a CYP2C9 substrate, increases diclofenac plasma levels by 75% and prolongs the half-life by 32.5% (97931). Animal research also shows that pretreatment with quercetin increases plasma levels and prolongs the half-life of losartan (Cozaar), a substrate of CYP2C9 (100968). Furthermore, laboratory research shows that quercetin inhibits CYP2C9 (15549,16433). |
Theoretically, concomitant use might increase the levels and adverse effects of CYP2D6 substrates.
|
Theoretically, concomitant use might alter the effects and adverse effects of CYP3A4 substrates.
A small clinical study in healthy volunteers shows that pretreatment with quercetin increases plasma levels and prolongs the half-life of a single dose of cyclosporine (Neoral, Sandimmune), a substrate of CYP3A4 (16434). Animal research also shows that pretreatment with quercetin increases plasma levels and prolongs the half-life of losartan (Cozaar) and quetiapine (Seroquel), substrates of CYP3A4 (100968,104228). Other laboratory research also shows that quercetin inhibits CYP3A4 (15549,16433,16435). However, one clinical study shows that quercetin can increase the metabolism of midazolam, a substrate of CYP3A4, and decrease serum concentrations of midazolam by about 24% in some healthy individuals, suggesting possible induction of CYP3A4 (91573).
|
Theoretically, concomitant use might increase the levels and adverse effects of diclofenac.
A small clinical study in healthy volunteers shows that taking quercetin 500 mg twice daily for 10 days prior to taking diclofenac increases diclofenac plasma levels by 75% and prolongs the half-life by 32.5%. This is thought to be due to inhibition of CYP2C9 by quercetin (97931). |
Theoretically, concomitant use might increase the effects and adverse effects of losartan and decrease the effects of its active metabolite.
Animal research shows that pretreatment with quercetin increases plasma levels and prolongs the half-life of losartan (Cozaar) while decreasing plasma levels of losartan's active metabolite. This metabolite, which is around 10-fold more potent than losartan, is the result of cytochrome P450 (CYP) 2C9- and CYP3A4-mediated transformation of losartan. Additionally, in vitro research shows that quercetin may inhibit P-glycoprotein-mediated efflux of losartan from the intestines, resulting in increased absorption of losartan (100968). These results suggest that concomitant use of quercetin and losartan might increase systemic exposure to losartan while also decreasing plasma concentrations of losartan's active and more potent metabolite. |
Theoretically, concomitant use might decrease the levels and effects of midazolam.
A small clinical study in healthy volunteers shows that quercetin can increase the metabolism of midazolam, with a decrease in AUC of about 24% (91573). |
Theoretically, quercetin might increase the effects and adverse effects of mitoxantrone.
In vitro research shows that quercetin increases the intracellular accumulation and cytotoxicity of mitoxantrone, possibly through inhibition of breast cancer resistance protein (BCRP), of which mitoxantrone is a substrate (107897). So far, this interaction has not been reported in humans.
|
Theoretically, concomitant use might increase the effects and adverse effects of OAT1 substrates.
In vitro research shows that quercetin is a strong non-competitive inhibitor of OAT1, with half-maximal inhibitory concentration (IC50) values less than 10 mcM (104454). So far, this interaction has not been reported in humans. |
Theoretically, concomitant use might increase the effects and adverse effects of OAT3 substrates.
|
Theoretically, concomitant use might increase the effects and adverse effects of OATP substrates.
In vitro evidence shows that quercetin can inhibit organic anion-transporting peptide (OATP) 1B1-mediated uptake of estrone-3-sulfate and pravastatin (91581). Furthermore, clinical research in healthy males shows that intake of quercetin along with pravastatin increases the AUC of pravastatin by 24%, prolongs its half-life by 14%, and decreases its apparent clearance by 18%, suggesting that quercetin modestly inhibits the uptake of pravastatin in hepatic cells (91581). |
Theoretically, concomitant use might alter the effects and adverse effects of P-glycoprotein substrates.
There is preliminary evidence that quercetin inhibits the gastrointestinal P-glycoprotein efflux pump, which might increase the bioavailability and serum levels of drugs transported by the pump (16433,16434,16435,100968,104228). A small study in healthy volunteers reported that pretreatment with quercetin increased bioavailability and plasma levels after a single dose of cyclosporine (Neoral, Sandimmune) (16434). Also, two small studies have shown that quercetin might decrease the absorption of talinolol, a substrate transported by the gastrointestinal P-glycoprotein efflux pump (91579,91580). However, in another small study, several days of quercetin treatment did not significantly affect the pharmacokinetics of saquinavir (Invirase) (16433). The reason for these discrepancies is not entirely clear (91580). Until more is known, use quercetin cautiously in combination with P-glycoprotein substrates. |
Theoretically, concomitant use might increase the effects and adverse effects of pravastatin.
In vitro evidence shows that quercetin can inhibit OATP 1B1-mediated uptake of pravastatin (91581). Also, preliminary clinical research in healthy males shows that intake of quercetin along with pravastatin increases the maximum concentration of pravastatin by 24%, prolongs its half-life by 14%, and decreases its apparent clearance by 18%, suggesting that quercetin modestly inhibits the uptake of pravastatin in hepatic cells (91581).
|
Theoretically, quercetin might increase the effects and adverse effects of prazosin.
In vitro research shows that quercetin inhibits the transcellular efflux of prazosin, possibly through inhibition of breast cancer resistance protein (BCRP), of which prazosin is a substrate. BCRP is an ATP-binding cassette efflux transporter in the intestines, kidneys, and liver (107897). So far, this interaction has not been reported in humans.
|
Theoretically, concomitant use might increase the effects and adverse effects of quetiapine.
Animal research shows that pretreatment with quercetin can increase plasma levels of quetiapine and prolong its clearance, possibly due to inhibition of cytochrome P450 3A4 (CYP3A4) by quercetin. Additionally, the brain-to-plasma ratio of quetiapine concentrations increased, possibly due to inhibition of P-glycoprotein at the blood-brain barrier (104228). This interaction has not been reported in humans.
|
Theoretically, concomitant use might inhibit the effects of quinolone antibiotics.
In vitro, quercetin binds to the DNA gyrase site on bacteria (481), which may interfere with the activity of quinolone antibiotics.
|
Theoretically, quercetin might increase the effects and adverse effects of sulfasalazine.
Animal research shows that quercetin increases the maximum serum concentration (Cmax) and area under the curve (AUC) of sulfasalazine, possibly through inhibition of breast cancer resistance protein (BCRP), of which sulfasalazine is a substrate (107897). So far, this interaction has not been reported in humans.
|
Theoretically, quercetin may increase the risk of bleeding if used with warfarin.
Animal and in vitro studies show that quercetin might increase serum levels of warfarin (17213,109619). Quercetin and warfarin have the same human serum albumin (HSA) binding site, and in vitro research shows that quercetin has stronger affinity for the HSA binding site and can theoretically displace warfarin, causing higher serum levels of warfarin (17213). Animal research shows that taking quercetin for 2 weeks before initiating warfarin increases the maximum serum level of warfarin by 30%, the half-life by 10%, and the overall exposure by 63% when compared with control. Concomitant administration of quercetin and warfarin, without quercetin pre-treatment, also increased these measures, but to a lesser degree. Researchers theorize that inhibition of CYP3A4 by quercetin may explain these effects (109619). So far, this interaction has not been reported in humans.
|
Resveratrol may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
|
Theoretically, resveratrol might increase levels of drugs metabolized by CYP1A1.
|
Theoretically, resveratrol might increase levels of drugs metabolized by CYP1A2.
In vitro research shows that resveratrol can inhibit CYP1A2 enzymes (21733). However, this interaction has not been reported in humans.
|
Theoretically, resveratrol might increase levels of drugs metabolized by CYP1B1.
In vitro research shows that resveratrol can inhibit CYP1B1 enzymes (70834). However, this interaction has not been reported in humans.
|
Theoretically, resveratrol might increase levels of drugs metabolized by CYP2C19.
In vitro research shows that resveratrol can inhibit CYP2C19 enzymes (70896). However, this interaction has not been reported in humans.
|
Resveratrol might increase levels of drugs metabolized by CYP2E1.
In vitro research suggests that resveratrol inhibits CYP2E1 isoenzyme (7864,70896). Also, a pharmacokinetic study shows that taking resveratrol 500 mg daily for 10 days prior to taking a single dose of chlorzoxazone 250 mg increases the maximum concentration of chlorzoxazone by about 54%, the area under the curve of chlorzoxazone by about 72%, and the half-life of chlorzoxazone by about 35% (95824). Chlorzoxazone is used as a probe drug for CYP2E1.
|
Theoretically, resveratrol might increase levels of drugs metabolized by CYP3A4.
|
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
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.
|
Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
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.
|
Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
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.
|
Theoretically, the antioxidant effects of vitamin C might reduce the effectiveness of antitumor antibiotics.
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.
|
Acidification of the urine by vitamin C might increase aspirin levels.
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.
|
Acidification of the urine by vitamin C might increase choline magnesium trisalicylate levels.
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.
|
Vitamin C might increase blood levels of estrogens.
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.
|
Theoretically, vitamin C might decrease levels of fluphenazine.
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.
|
Vitamin C can modestly reduce indinavir levels.
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).
|
Vitamin C can increase levothyroxine absorption.
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).
|
Vitamin C might decrease the beneficial effects of niacin on high-density lipoprotein (HDL) cholesterol levels.
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.
|
Acidification of the urine by vitamin C might increase salsalate levels.
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.
|
High-dose vitamin C might reduce the levels and effectiveness of warfarin.
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.
|
Below is general information about the adverse effects of the known ingredients contained in the product Resveratrol Synergy. 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, the whole fruit, as well as the seed, fruit, and leaf extracts, seem to be well tolerated.
Topically, grape seed extracts seem to be well tolerated.
Most Common Adverse Effects:
Orally: Abdominal pain, diarrhea, dry mouth, dyspepsia, headache, joint pain, and nausea.
Serious Adverse Effects (Rare):
Orally: Anaphylaxis to grape skin has been reported.
Dermatologic ...Orally, mild hair thinning has been reported in a patient taking a specific grape leaf extract AS195 KG) (2538). Urticaria (hives) has also been reported with this same extract (53206). Cases of contact dermatitis have been reported in grape workers, including those working in California vineyards (53270,53272,53275).
Gastrointestinal ...Orally, abdominal pain and nausea have been reported with use of grape seed extract, but these effects typically occur at rates similar to placebo (9182,13162). In a case report of a 57-year-old man, intermittent nausea, vomiting, and diarrhea occurred over a 10-day period and improved once grape seed extract was stopped (96764). Gastrointestinal adverse effects have also been reported with use of a different grape seed extract (Entelon, Hanlim Pharm). However, the specific types of gastrointestinal effects were not described (100954). A specific grape leaf extract AS195 (Antistax, Boehringer Ingelheim Pharma GmbH & Co. KG) has reportedly caused flatulence, mild constipation, gastrointestinal discomfort, diarrhea, dyspepsia, dry mouth, and retching (2538,52985,53206). Diarrhea, gastrointestinal distress, indigestion, and aversion to taste have been reported with use of Concord grape juice (52972,53166,53175,53181,53199). Loose stools have been reported in a clinical trial of grape pomace (99270). Bowel obstruction caused by intact grapes and grape seeds has been described in case reports (53241,53284,53278). Excessive consumption of grapes, dried grapes, raisins, or sultanas might cause diarrhea due to laxative effects (4201).
Hematologic ...Orally, one case of leg hematoma following a minor trauma was reported in a person using grape leaf extract (2538). Also, one case of bruising was reported in a person drinking Concord grape juice daily for 2 weeks (52972).
Immunologic ...Orally, there is one report of an anaphylactic reaction to oral grape skin extract, which included urticaria and angioedema (4073).
Musculoskeletal ...Orally, musculoskeletal disorders, including back pain, have been reported with use of a specific grape leaf extract AS195 KG) (2538,53206). Joint pain and lumbago have been reported with use of grape seed extract, but these effects occur at rates similar to placebo (91541).
Neurologic/CNS ...Orally, headache has been reported with use of grape seed extract, but this effect occurs at rates similar to placebo (9182,91541). A specific grape leaf extract AS195 (Antistax, Boehringer Ingelheim Pharma GmbH & Co. KG) has reportedly caused dizziness, tiredness, headache, and sleep problems (2538,53206). As a class, nervous system adverse effects have been reported with use of a specific grape seed extract (Entelon, Hanlim Pharm). However, the specific types of adverse neurologic effects were not described (100954).
Ocular/Otic ...Orally, ocular adverse effects have been reported with use of a specific grape seed extract (Entelon, Hanlim Pharm). However, the specific types of ocular adverse effects were not described (100954).
Pulmonary/Respiratory ...Orally, nasopharyngitis and oropharyngeal pain have been reported with use of a specific grape leaf extract AS195 KG) (53206). Sore throat, cough, allergic rhinitis, and nasopharyngitis have been reported with use of grape seed extract, but these effects occur at rates similar to placebo (9182,91541). One case report describes a 16-year-old female who developed increased levels of immunoglobulin E (IgE) following skin-prick exposure to grape vine pollen, as well as positive test responses following bronchial and conjunctival provocation (53301). Reduced forced vital capacity has been described in California grape workers (53080,53081). Occupational eosinophilic lung was diagnosed in a grape grower with a history of asthma. Respiratory exposure to sulfites in grape was implicated as the cause of the adverse reaction (53285).
Other
...Orally, grape products can cause adverse effects due to contamination with pesticides or mycotoxins.
Some evidence has shown that pesticides used in vineyards may remain on grape surfaces post-harvesting. For example, the fungicide folpet sprayed on grapevines has been shown to remain on the grape surface. Although there was minimal penetration of the epicuticular wax, it showed high resistance to washing (52935). Carbaryl has been identified in over 58% of juice samples collected in Canada. This pesticide reportedly occurred more frequently in grape than in other juices. However, estimates of short-term intake were below proposed acute reference doses (53003).
Ochratoxin A is a mycotoxin that is suspected to be nephrotoxic, teratogenic, hepatotoxic and carcinogenic and has been identified in grape juice, frozen grape pulps, and red and white wine sold in Rio de Janeiro, Brazil. However, the highest levels identified in grape products were lower than the established virtually safe dose of 5 ng/kg of body weight daily (53010,53004). Ochratoxin A has also been identified in red, but not white, grape juice marketed in Switzerland, Canada, and the U.S. (53292,53020).
General ...Orally and intravenously, quercetin seems to be well tolerated in appropriate doses. Topically, no adverse effects have been reported. However, a thorough evaluation of safety outcomes has not been conducted.
Gastrointestinal ...Intravenous administration of quercetin is associated with nausea and vomiting (9564).
Neurologic/CNS ...Orally, quercetin may cause headache and tingling of the extremities (481,111500). Intravenously, quercetin may cause pain at the injection site. Injection pain can be minimized by premedicating patients with 10 mg of morphine and administering amounts greater than 945 mg/m2 over 5 minutes (9564). In addition, intravenous administration of quercetin is associated with flushing and sweating (9564).
Pulmonary/Respiratory ...Intravenous administration of quercetin at doses as high as 2000 mg/m2 is associated with dyspnea that may persist for up to 5 minutes (9564).
Renal ...Intravenously, nephrotoxicity has been reported with quercetin in amounts greater than 945 mg/m2 (9563,9564,70304).
General
...In foods, resveratrol is well tolerated.
When used orally in higher doses, as well as topically or intranasally, resveratrol seems to be well tolerated.
Most Common Adverse Effects:
Orally: Diarrhea, gastrointestinal discomfort, and loose stools.
Dermatologic
...Orally, there is one case of a pruritic skin rash that occurred in a clinical trial.
The rash resolved two weeks after stopping resveratrol (109163).
Topically, a case of allergic contact dermatitis has been reported after applying a facial cream (Resveratrol BE, Skinceuticals) containing aqueous resveratrol 1% in combination with Baikal skullcap root extract 0.5%. Patch testing identified a positive reaction to both ingredients (110024).
Gastrointestinal ...Orally, mild gastrointestinal discomfort with increased diarrhea or loose stools has been reported, especially when resveratrol is taken in doses of 2. 5-5 grams daily (71042,71052,91327,95830,109163,109164,109167).
Hematologic ...In one clinical study, a patient developed severe febrile leukopenia and thrombocytopenia after taking oral resveratrol 500 mg three times daily for 10 days. Upon re-exposure to resveratrol, febrile leukopenia recurred (109163).
Musculoskeletal ...Orally, resveratrol has been associated with muscle cramps in patients on peritoneal dialysis. The causality of this adverse effect has not been established (95830).
Neurologic/CNS ...Orally, resveratrol has been associated with headache, fatigue, and memory loss in patients on peritoneal dialysis. The causality of these adverse effects has not been established (95830).
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).