Major interaction on record — check this product against your medications before combining. Based on 4 of 6 ingredients. Check your meds →
Dietary supplement

Whole Grape Extract Ingredients & Drug Interactions

by Life Extension

Capsule Category: Other Combinations
Most serious interaction: Major
The interaction bottom line Most serious interaction: Major

Whole Grape Extract is a dietary supplement by Life Extension with 6 active ingredients. Its ingredients are commonly taken for bone health and osteoporosis prevention, dietary calcium deficiency, heartburn relief (calcium carbonate antacids).Based on those ingredients, 1,078 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Leucoselect, Trans-Resveratrol, Vitamin C. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of Whole Grape Extract by Life Extension

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

What’s inside

Partial disclosure
Ingredient Transparency · database check
Partial

Most active ingredients list an amount, but at least one is hidden in a blend or missing.

Why this rating?
  • The label discloses an exact amount for 3 of its 6 active ingredients.
  • “Oligomeric Proanthocyanidins Proprietary Blend:” is a proprietary blend — the label gives one combined amount (150 mg) without saying how much of each component you get.

This product contains six active ingredients: calcium, vitamin C, trans-resveratrol, a proprietary blend of oligomeric proanthocyanidins (Masquelier's 2 Original OPCs and Leucoselect), and Guardenol. The formula also includes four inactive ingredients — vegetable cellulose, microcrystalline cellulose, silica, and vegetable stearate — which are fillers and capsule materials.

Calcium supports bone and metabolic health. Vitamin C is an antioxidant and immune supporter.

Trans-resveratrol is a polyphenol from grapes. The proanthocyanidins (OPCs) and grape extracts Leucoselect and Guardenol are plant compounds derived from grape seeds and skins, thought to have antioxidant properties.

Does it work?

Not established
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Not established

The graded evidence we hold for these ingredients covers different conditions than the ones this product is marketed for, so there's no established rating for its stated use.

Why this rating?
  • The label markets this product for: Antioxidant support and heart health.
  • We looked for evidence on: Atherosclerosis, Cardiovascular disease (CVD), Dyslipidemia, Exercise-induced muscle damage, Vascular endothelial function, Oxidative stress — and 1 related terms.
  • The closest evidence on file: Resveratrol is rated "Possibly Ineffective" for Cardiovascular disease (CVD) (Natural Medicines).
  • Also on file: Vitamin C is rated "Possibly Ineffective" for Atherosclerosis, Cardiovascular disease (CVD).
  • Also on file: Calcium is rated "Ineffective" for Cardiovascular disease (CVD).

Evidence for these ingredients varies. Calcium is effective for kidney failure, dyspepsia (indigestion), low blood calcium (hypocalcemia), high potassium (hyperkalemia), and likely effective for osteoporosis.

Vitamin C is effective for vitamin C deficiency and possibly effective for anemia of chronic disease, atrial fibrillation, cataracts, and infections triggered by exercise. Trans-resveratrol is possibly effective for obesity and allergic rhinitis (hay fever), but possibly ineffective for heart disease and high cholesterol.

The grape extracts are possibly effective for chronic venous insufficiency (leg swelling and pain) but possibly ineffective for nausea from chemotherapy, hay fever, and obesity. We hold no effectiveness data for Masquelier's 2 Original OPCs.

The evidence, ingredient by ingredient Calcium Vitamin C Resveratrol Grape

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 4 of the 4 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 4 of 4.
  • General safety write-ups exist for 4 of 4.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Calcium is generally well tolerated at recommended doses; the most common side effects are belching, constipation, diarrhea, and stomach upset. High doses raise concerns about kidney stones and a rare condition called calciphylaxis.

Very high intake (over 1500–2000 mg daily) has been associated in some research with increased prostate cancer risk and possibly heart disease, though these findings remain debated. Calcium is likely safe in pregnancy and lactation at normal amounts.

Vitamin C is well tolerated; common effects at high doses include stomach cramps, heartburn, and diarrhea. Resveratrol is generally well tolerated in typical doses but may cause diarrhea and digestive discomfort; long-term safety is not fully established, and it should be avoided in pregnancy and breastfeeding due to insufficient data.

The grape extracts are generally well tolerated; rare side effects include abdominal pain, diarrhea, headache, joint pain, and one case of anaphylaxis to grape skin. Resveratrol is likely safe in pregnancy, but the grape extracts should be avoided during pregnancy and breastfeeding due to limited safety information.

Side effects, ingredient by ingredient Calcium Vitamin C Resveratrol Grape

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 4 of the 4 matched ingredients can interact with medications — Resveratrol, Grape, Calcium, Vitamin C.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; cancer treatments; heart-rhythm medications; lithium.
  • For scale: 1,079 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

You should double-check integrase inhibitors (dolutegravir, elvitegravir), thyroid medications (levothyroxine), blood thinners and antiplatelet drugs, intravenous ceftriaxone, estrogens, heart medications (diltiazem), and cyclosporine. High-dose vitamin C may also affect warfarin and chemotherapy drugs.

Check your exact medications with the search tool on this page.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glancePartially disclosed formula with no established evidence rating for its marketed use. Major medication interactions have been identified, and safety information is well characterized.

If you take HIV medications, thyroid drugs, blood thinners, or heart medications, check your exact prescriptions with the tool below before starting this product — the interaction concerns are real. Otherwise, it's generally well tolerated at recommended doses.

Talk to your pharmacist about your current medications and any prostate or heart concerns before you add it.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 5 of 6 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Sep 22, 2016.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Whole Grape Extract, straight from the product label.

Brand Life Extension
Barcode (UPC) 737870109167
Net contents 60 Vegetarian Capsule(s)
Market status On market
Date entered into DSLD Sep 22, 2016
DSLD ID 64473
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years)
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Whole Grape Extract by Life Extension, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Vegetarian Capsule(s)
Maximum serving Sizes:
1 Vegetarian Capsule(s)
UPC/BARCODE
737870109167
IngredientAmount% DV
Calcium10 mg1%
Vitamin C100 mg167%
Trans-Resveratrol25 mg--
Oligomeric Proanthocyanidins Proprietary Blend:150 mg--
Masquelier’s 2 Original OPCs0 NP--
Leucoselect0 NP--
Guardenol0 NP--

Other ingredients: Vegetable Cellulose, Microcrystalline Cellulose, Silica, Vegetable Stearate

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Brand IP Statement(s)

3- Leucoselect is a registered trademark of Indena S.p.A.

1- Free Radical Scavenging/Antioxidant Effect: protected for use as an antioxidant under US Patent 4,698,360.

2- MASQUELIER's is a registered trademark of International Nutrition Company BV (INC), Loosdrecht, The Netherlands.

General

QE01091F

Formula

Standardized Resveratrol, Grape Seed, and Red Wine Polyphenols

FDA Statement of Identity

Dietary Supplement

General Statements

To report a serious adverse event or obtain product information, contact 1-866-280-2852.

Scan for product info

Suggested/Recommended/Usage/Directions

Read the entire label and follow the directions carefully prior to use. DIRECTIONS: Take one (1) capsule daily with or without food, or as recommended by a healthcare practitioner.

Storage

Store tightly closed in a cool, dry place.

Precautions

WARNINGS: ~ KEEP OUT OF REACH OF CHILDREN.

~ DO NOT EXCEED RECOMMENDED DOSE. ~ Do not purchase if outer seal is broken or damaged.

~ When using nutritional supplements, please consult with your physician if you are undergoing treatment for a medical condition or if you are pregnant or lactating.

FDA Disclaimer Statement

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

See for yourself

Whole Grape Extract by Life Extension label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

What’s inside

The Ingredients in Whole Grape Extract by Life Extension

These are the 6 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Vegetarian Capsule(s) Dosage formCapsule Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Calcium

Interacts with
168 drugs
10 mg per serving Form: Calcium Ascorbate

Calcium is an essential mineral your body needs for strong bones, nerve signaling, and muscle function, and supplements can help fill gaps when diet f...

Calcium monograph & interactions

Vitamin C

Interacts with
207 drugs
100 mg per serving Form: Calcium Ascorbate

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for im...

Vitamin C monograph & interactions

Trans-Resveratrol

Interacts with
822 drugs
25 mg per serving Form: Glycosides, Japanese Knotweed, Red Grape extracts

Resveratrol is a plant compound found in red grapes, berries, and peanuts that is popular for heart health, anti-aging, and antioxidant support. While...

Trans-Resveratrol monograph & interactions

Oligomeric Proanthocyanidins Proprietary Blend:

150 mg per serving

Other (inactive) ingredients: Vegetable Cellulose, Microcrystalline Cellulose, Silica, Vegetable Stearate. These complete the product’s ingredient list but are not active constituents.

Interaction report

Whole Grape Extract by Life Extension Drug Interactions

Want to check YOUR meds against Whole Grape Extract?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

Go to the checker
1,078Drugs
7 Major 1,032 Moderate 39 Minor

Ingredients driving the most interactions

Vitamin C 207
Calcium 168

Each ingredient & the kinds of drugs it affects

For each ingredient in Whole Grape Extract with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Leucoselect9 drug types · 910 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, grape extracts may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
In vitro evidence suggests that grape extracts might decrease platelet aggregation.

Likelihood Possible Evidence D
Cyclosporine (Neoral, Sandimmune)

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. Separate doses of grape juice and cyclosporine by at least 2 hours to avoid this interaction.

Likelihood Possible Evidence B
Cytochrome P450 1A2 (Cyp1A2) Substrates

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.

Likelihood Possible Evidence B
Cytochrome P450 2D6 (Cyp2D6) Substrates

Theoretically, grape seed extract may increase the levels of CYP2D6 substrates.
In vitro evidence suggests that grape seed extract might inhibit CYP2D6 enzymes. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2E1 (Cyp2E1) Substrates

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. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

It is unclear if grape seed extract inhibits or induces CYP3A4; research is conflicting.
In vitro evidence suggests that grape seed extract might inhibit CYP3A4 enzymes. However, evidence from animal research shows that grape seed extract may induce CYP3A4 in the liver. So far, these interactions have not been reported in humans.

Likelihood Possible Evidence D
Midazolam (Versed)

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.

Likelihood Possible Evidence D
Phenacetin

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).

Likelihood Possible Evidence B
Cytochrome P450 2C9 (Cyp2C9) Substrates

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. 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. The effects of continued grape juice consumption are unclear.

Likelihood Unlikely Evidence D

Trans-Resveratrol5 drug types · 822 drugs

Anticoagulant/Antiplatelet Drugs

Resveratrol may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Resveratrol seems to have antiplatelet effects.

Likelihood Possible Evidence D
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, resveratrol might increase levels of drugs metabolized by CYP1A2.
In vitro research shows that resveratrol can inhibit CYP1A2 enzymes. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2C19 (Cyp2C19) Substrates

Theoretically, resveratrol might increase levels of drugs metabolized by CYP2C19.
In vitro research shows that resveratrol can inhibit CYP2C19 enzymes. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2E1 (Cyp2E1) Substrates

Resveratrol might increase levels of drugs metabolized by CYP2E1.
In vitro research suggests that resveratrol inhibits CYP2E1 isoenzyme. 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%. Chlorzoxazone is used as a probe drug for CYP2E1.

Likelihood Probable Evidence B
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, resveratrol might increase levels of drugs metabolized by CYP3A4.
In vitro research shows that resveratrol can inhibit the CYP3A4 enzyme. However, clinical research shows that taking resveratrol 3000 mg daily for 8 weeks does not necessitate dose adjustments to medications metabolized by CYP3A4.

Likelihood Possible Evidence D

Vitamin C13 drug types · 207 drugs

Alkylating Agents

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. 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. More evidence is needed to determine what effect, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Aluminum

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. In people with normal renal function, urinary excretion of aluminum will likely increase, making aluminum retention and toxicity unlikely. 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.

Likelihood Probable Evidence B
Antitumor Antibiotics

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. 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. More evidence is needed to determine what effects, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Estrogens

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. 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. 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. Monitor these patients for estrogen-related side effects.

Likelihood Probable Evidence B
Fluphenazine (Prolixin)

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. The mechanism is not known, and there is no further data to confirm this interaction.

Likelihood Possible Evidence D
Indinavir (Crixivan)

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.

Likelihood Probable Evidence B
Levothyroxine (Synthroid, Others)

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.

Likelihood Probable Evidence B
Warfarin (Coumadin)

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. There are reports of two people who took up to 16 grams daily of vitamin C and had a reduction in prothrombin time. Lower doses of 5-10 grams daily can also reduce warfarin absorption. In many cases, this does not seem to be clinically significant. 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). 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.

Likelihood Possible Evidence D
Acetaminophen (Tylenol, Others)

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. This effect is not likely to be clinically significant.

Likelihood Probable Evidence B
Aspirin

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. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction is not clinically significant.

Likelihood Possible Evidence B
Choline Magnesium Trisalicylate (Trilisate)

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. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B
Niacin

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. 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.

Likelihood Possible Evidence A
Salsalate (Disalcid)

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. However, short-term use of up to 6 grams/day vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B

Calcium18 drug types · 168 drugs

Ceftriaxone (Rocephin)

Co-administration of intravenous calcium and ceftriaxone can result in precipitation of a ceftriaxone-calcium salt in the lungs and kidneys.
Avoid administering intravenous calcium in any form, such as parenteral nutrition or Lactated Ringers, within 48 hours of intravenous ceftriaxone. Case reports in neonates show that administering intravenous ceftriaxone and calcium can result in precipitation of a ceftriaxone-calcium salt in the lungs and kidneys. In several cases, neonates have died as a result of this interaction. So far there are no reports in adults; however, there is still concern that this interaction might occur in adults.

Likelihood Probable Evidence D
Dolutegravir (Tivicay)

Calcium seems to reduce levels of dolutegravir.
Advise patients to take dolutegravir either 2 hours before or 6 hours after taking calcium supplements. Pharmacokinetic research suggests that taking calcium carbonate 1200 mg concomitantly with dolutegravir 50 mg reduces plasma levels of dolutegravir by almost 40%. Calcium appears to decrease levels of dolutegravir through chelation.

Likelihood Probable Evidence B
Elvitegravir (Vitekta)

Calcium seems to reduce levels of elvitegravir.
Advise patients to take elvitegravir either 2 hours before or 2 hours after taking calcium supplements. Pharmacokinetic research suggests that taking calcium along with elvitegravir can reduce blood levels of elvitegravir through chelation.

Likelihood Probable Evidence B
Aluminum

Calcium citrate might increase aluminum absorption and toxicity. Other types of calcium do not increase aluminum absorption.
Calcium citrate can increase the absorption of aluminum when taken with aluminum hydroxide. The increase in aluminum levels may become toxic, particularly in individuals with kidney disease. However, the effect of calcium citrate on aluminum absorption is due to the citrate anion rather than calcium cation. Calcium acetate does not appear to increase aluminum absorption.

Likelihood Possible Evidence B
Bictegravir/Emtricitabine/Tenofovir Alafenamide (Biktarvy)

Calcium might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption when taken in a fasting state.
Advise patients that bictegravir/emtricitabine/tenofovir alafenamide and calcium can be taken together if taken with food. However, if taken on an empty stomach, bictegravir/emtricitabine/tenofovir alafenamide should not be taken with, or 2 hours after, calcium containing products.

Likelihood Probable Evidence D
Bisphosphonates

Calcium reduces the absorption of bisphosphonates.
Advise patients to take bisphosphonates at least 30 minutes before calcium, but preferably at a different time of day. Calcium supplements decrease absorption of bisphosphonates.

Likelihood Probable Evidence C
Calcipotriene (Dovonex)

Taking calcipotriene with calcium might increase the risk for hypercalcemia.
Calcipotriene is a vitamin D analog used topically for psoriasis. It can be absorbed in sufficient amounts to cause systemic effects, including hypercalcemia. Theoretically, combining calcipotriene with calcium supplements might increase the risk of hypercalcemia.

Likelihood Possible Evidence B
Digoxin (Lanoxin)

Using intravenous calcium with digoxin might increase the risk of fatal cardiac arrhythmias.
Hypercalcemia increases the risk of fatal cardiac arrhythmias with digoxin. However, one retrospective analysis of clinical data suggests that intravenous calcium does not increase the risk of dysrhythmias or mortality in patients receiving digoxin.

Likelihood Possible Evidence B
Diltiazem (Cardizem, Others)

Theoretically, calcium may reduce the therapeutic effects of diltiazem.
Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically, calcium might increase this risk of hypercalcemia and reduce the effectiveness of diltiazem.

Likelihood Probable Evidence D
Levothyroxine (Synthroid, Others)

Calcium seems to reduce the absorption and effectiveness of levothyroxine.
Advise patients to take levothyroxine and calcium supplements at least 4 hours apart. Calcium reduces levothyroxine absorption, probably by forming insoluble complexes. Calcium carbonate supplements reduce effectiveness of levothyroxine in patients with hypothyroidism.

Likelihood Probable Evidence B
Lithium

Theoretically, concomitant use of calcium and lithium may increase this risk of hypercalcemia.
Clinical research suggests that long-term use of lithium may cause hypercalcemia in 10% to 60% of patients. Theoretically, concomitant use of lithium and calcium supplements may further increase this risk.

Likelihood Possible Evidence B
Quinolone Antibiotics

Calcium seems to reduce the absorption of quinolone antibiotics.
Advise patients to take oral quinolones at least 2 hours before or 4-6 hours after calcium supplements or calcium-fortified foods. Taking calcium at the same time as oral quinolones can reduce quinolone absorption. Calcium binds to quinolones in the gut.

Likelihood Probable Evidence B
Raltegravir (Isentress)

Calcium may reduce levels of raltegravir.
Pharmacokinetic research shows that taking a single dose of calcium carbonate 3000 mg along with raltegravir 400 mg twice daily modestly decreases the mean area under the curve of raltegravir, but the decrease does not necessitate a dose adjustment of raltegravir. However, a case of elevated HIV-1 RNA levels and documented resistance to raltegravir has been reported for a patient taking calcium carbonate 1 gram three times daily plus vitamin D3 (cholecalciferol) 400 IU three times daily in combination with raltegravir 400 mg twice daily for 11 months. It is thought that calcium reduced raltegravir levels by chelation, leading to treatment failure.

Likelihood Possible Evidence B
Sotalol (Betapace)

Calcium seems to reduce the absorption of sotalol.
Advise patients to separate doses by at least 2 hours before or 4-6 hours after calcium. Calcium appears to reduce the absorption of sotalol, probably by forming insoluble complexes.

Likelihood Possible Evidence B
Tetracycline Antibiotics

Calcium seems to reduce the absorption of tetracycline antibiotics.
Advise patients to take oral tetracyclines at least 2 hours before, or 4-6 hours after calcium supplements. Taking calcium at the same time as oral tetracyclines can reduce tetracycline absorption. Calcium binds to tetracyclines in the gut.

Likelihood Probable Evidence C
Thiazide Diuretics

Taking calcium along with thiazides might increase the risk of hypercalcemia and renal failure.
Thiazides reduce calcium excretion by the kidneys. Using thiazides along with moderately large amounts of calcium carbonate increases the risk of milk-alkali syndrome (hypercalcemia, metabolic alkalosis, renal failure). Patients may need to have their serum calcium levels and/or parathyroid function monitored regularly.

Likelihood Probable Evidence C
Verapamil (Calan, Others)

Theoretically, calcium may reduce the therapeutic effects of verapamil.
Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically, use of calcium supplements may increase this risk of hypercalcemia and reduce the effectiveness of verapamil.

Likelihood Probable Evidence D
Calcium Channel Blockers

Intravenous calcium may decrease the effects of calcium channel blockers; oral calcium is unlikely to have this effect.
Intravenous calcium is used to decrease the effects of calcium channel blockers in the management of overdose. Intravenous calcium gluconate has been used before intravenous verapamil (Isoptin) to prevent or reduce the hypotensive effects without affecting the antiarrhythmic effects. But there is no evidence that dietary or supplemental calcium when taken orally interacts with calcium channel blockers.

Likelihood Unlikely Evidence D
The maker

Brand information

Manufacturer and brand details for Whole Grape Extract, from the product label.

Life Extension

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Name
Quality Supplements and Vitamins, Inc.
City
Ft. Lauderdale
State
FL
ZipCode
33309
Phone Number
866-280-2852
Web Address
www.lef.org
Pharmacist Counseling Corner

Whole Grape Extract by Life Extension: Common Questions

Does Whole Grape Extract by Life Extension interact with any medications?
Yes. Based on its ingredients, Whole Grape Extract has a known interaction with 1,078 medications, including 7 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Whole Grape Extract contains 6 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Can I take this if I'm pregnant or breastfeeding?
For pregnancy: calcium and vitamin C are likely safe at normal doses, but resveratrol should be avoided due to insufficient safety data, and the grape extracts aren't recommended. For breastfeeding: calcium and vitamin C are safe at recommended amounts, but resveratrol and the grape extracts lack enough safety information — talk to your doctor or pharmacist for personalized advice.
What are the most common side effects?
From calcium, you might experience belching, constipation, diarrhea, or stomach upset. Vitamin C at high doses can cause stomach cramps, heartburn, or diarrhea. The grape extracts may cause abdominal pain, diarrhea, or headache. Most people tolerate it well at recommended doses.
Will this help my cholesterol or heart health?
Resveratrol is possibly ineffective for high cholesterol and heart disease according to our data. The grape extracts are possibly effective for chronic venous insufficiency — leg swelling and pain — but possibly ineffective for general cardiovascular health.
Is this good for bone health?
Calcium in this product is likely effective for osteoporosis. However, very high calcium intake over time has been linked in some research to increased heart disease risk, so stick to recommended doses and talk to your doctor if you're taking other calcium sources.
What are the grape extracts (OPCs) for?
The proanthocyanidins from grape seeds and skins are thought to be antioxidants. They're possibly effective for chronic venous insufficiency, a condition involving leg swelling and pain from poor circulation, but we found them possibly ineffective for chemotherapy nausea, allergies, and weight loss.
Can I take this with my other supplements?
That depends on what they contain. This product interacts with dozens of medications and other supplements through its calcium, vitamin C, and grape extracts. Use the medication checker on this page to verify your full regimen, and talk to your pharmacist.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Whole Grape Extract label
Sources

Sources & How We Checked

Whole Grape Extract's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 171 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

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See these in context on the Calcium monograph →

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Resveratrol 24 references
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  20. Lin CT, Sun XY, Lin AX. Supplementation with high-dose trans-resveratrol improves ultrafiltration in peritoneal dialysis patients: a prospective, randomized, double-blind study. Ren Fail. 2016;38(2):214-21. PubMed
  21. Li Q, Yang G, Xu H, Tang S, Lee WY. Effects of resveratrol supplementation on bone quality: a systematic review and meta-analysis of randomized controlled trials. BMC Complement Med Ther 2021;21(1):214. PubMed
  22. McCreary MR, Schnell PM, Rhoda DA. Randomized double-blind placebo-controlled proof-of-concept trial of resveratrol for outpatient treatment of mild coronavirus disease (COVID-19). Sci Rep 2022;12(1):10978. PubMed
  23. Abdelhaleem IA, Brakat AM, Adayel HM, Asla MM, Rizk MA, Aboalfetoh AY. The effects of resveratrol on glycemic control and cardiometabolic parameters in patients with T2DM: A systematic review and meta-analysis. Med Clin (Barc) 2022;158(12):576-585. PubMed
  24. Badaoui A. Allergic contact dermatitis to resveratrol and Scutellaria baicalensis root extract in a cosmetic product. Contact Dermatitis 2022.

See these in context on the Resveratrol monograph →

Grape 34 references
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  4. Chevallier A. The Encyclopedia of Medicinal Plants. London, UK: Dorling Kindersley, Ltd., 1996.
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  9. O'Byrne, D. J., Devaraj, S., Grundy, S. M., and Jialal, I. Comparison of the antioxidant effects of Concord grape juice flavonoids alpha-tocopherol on markers of oxidative stress in healthy adults. Am J Clin.Nutr. 2002;76(6):1367-1374.
  10. Schaefer, E., Peil, H., Ambrosetti, L., and Petrini, O. Oedema protective properties of the red vine leaf extract AS 195 (Folia vitis viniferae) in the treatment of chronic venous insufficiency. A 6-week observational clinical trial. Arzneimittelforschun PubMed
  11. Nishikawa, M., Ariyoshi, N., Kotani, A., Ishii, I., Nakamura, H., Nakasa, H., Ida, M., Nakamura, H., Kimura, N., Kimura, M., Hasegawa, A., Kusu, F., Ohmori, S., Nakazawa, K., and Kitada, M. Effects of continuous ingestion of green tea or grape seed extra
  12. de Lange, D. W., Scholman, W. L., Kraaijenhagen, R. J., Akkerman, J. W., and van de Wiel, A. Alcohol and polyphenolic grape extract inhibit platelet adhesion in flowing blood. Eur.J Clin.Invest 2004;34(12):818-824. PubMed
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  15. de Lange, D. W., Verhoef, S., Gorter, G., Kraaijenhagen, R. J., van de Wiel, A., and Akkerman, J. W. Polyphenolic grape extract inhibits platelet activation through PECAM-1: an explanation for the French paradox. Alcohol Clin.Exp.Res 2007;31(8):1308-1314 PubMed
  16. Etheridge, A. S., Black, S. R., Patel, P. R., So, J., and Mathews, J. M. An in vitro evaluation of cytochrome P450 inhibition and P-glycoprotein interaction with goldenseal, Ginkgo biloba, grape seed, milk thistle, and ginseng extracts and their constitu
  17. Krikorian, R., Nash, T. A., Shidler, M. D., Shukitt-Hale, B., and Joseph, J. A. Concord grape juice supplementation improves memory function in older adults with mild cognitive impairment. Br J Nutr. 2010;103(5):730-734. PubMed
  18. Ingersoll, G. L., Wasilewski, A., Haller, M., Pandya, K., Bennett, J., He, H., Hoffmire, C., and Berry, C. Effect of concord grape juice on chemotherapy-induced nausea and vomiting: results of a pilot study. Oncol.Nurs.Forum 2010;37(2):213-221. PubMed
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  30. Brito, FF., Martinez, A., Palacios, R., Mur, P., Gomez, E., Galindo, P. A., Borja, J., and Martinez, J. Rhinoconjunctivitis and asthma caused by vine pollen: a case report. J Allergy Clin Immunol 1999;103(2 Pt 1):262-266. PubMed
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  34. Moon SW, Shin YU, Cho H, Bae SH, Kim HK; and for the Mogen Study Group. Effect of grape seed proanthocyanidin extract on hard exudates in patients with non-proliferative diabetic retinopathy. Medicine (Baltimore) 2019;98(21):e15515. PubMed

See these in context on the Grape monograph →

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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

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