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Dietary supplement

Trans-Resveratrol Ingredients & Drug Interactions

by Vitacost

Trans-Resveratrol label
See full label image
Capsule Category: Botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Trans-Resveratrol against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Moderate

Trans-Resveratrol is a dietary supplement by Vitacost with 1 active ingredient. Its ingredients are commonly taken for source of resveratrol, heart and circulation support, inflammation.Based on those ingredients, 826 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Japanese Knotweed. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Trans-Resveratrol by Vitacost

Ask about any prescription or over-the-counter medication and we check it for interactions with Trans-Resveratrol by Vitacost — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Trans-Resveratrol by Vitacost

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

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 11, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product is a single-ingredient supplement: Japanese Knotweed extract (also called Hu Zhang), the source of resveratrol. The capsule itself contains inactive ingredients — hydroxypropyl methylcellulose and rice flour — which are binders and fillers.

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 — see Hu Zhang's own graded uses on its monograph.

Why this rating?
  • The label markets this product for: antioxidant protection and heart health.
  • We looked for evidence on: Unstable angina, cardiovascular health, free radical damage, cellular protection.
  • The closest evidence on file: Hu Zhang is rated "Insufficient Reliable Evidence To Rate" for Unstable angina (Natural Medicines).

The data we hold shows insufficient evidence to rate Japanese Knotweed for hepatitis, rheumatoid arthritis, wound healing, gout, osteoarthritis, or unstable angina. In other words, the research isn't established enough for us to say whether it works for these uses.

If you're considering it for a specific condition, that's worth discussing with your pharmacist or doctor.

The evidence, ingredient by ingredient Hu Zhang

How safe is it?

Some data gaps
Safety Information · database check
Some gaps

Safety data exists for these ingredients, but with some important gaps.

Why this rating?
  • We hold adverse-effect (side-effect) data for 0 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Japanese Knotweed is used in traditional medicine, but human safety data for supplements are limited. The ingredient contains emodin, which may cause digestive upset.

Pregnancy safety data are not sufficient — the evidence isn't there to know either way, so talk with your doctor or pharmacist before using it if you're pregnant. Breastfeeding safety data are also lacking, and some compounds in knotweed may affect the uterus or bowel, so it's best avoided while nursing unless you've talked it over with your provider.

Side effects, ingredient by ingredient Hu Zhang

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Hu Zhang.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs.
  • For scale: 827 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.

Before taking this product, check your exact medications against our drug interaction tool on this page. The biggest concerns are blood thinners and antiplatelet drugs (Moderate risk of increased bleeding), drugs metabolized by liver enzymes CYP1A2, CYP2C19, CYP3A4, and CYP2E1 (Moderate risk of raised drug levels), estrogen replacement therapy (Moderate risk), and carbamazepine/Tegretol (Minor risk).

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no established evidence rating for its marketed use. Moderate medication interactions have been identified, and some safety-information gaps remain.

If you take blood thinners, seizure medications, or drugs that rely on liver enzymes to be cleared, this product needs a medication check first — the interactions are theoretical but real enough to watch. Talk to your pharmacist before you start, especially if you're on any prescription medications.

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

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Oct 23, 2019.

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 Trans-Resveratrol, straight from the product label.

Brand Vitacost
Barcode (UPC) 844197012688
Net contents 60 Vegetarian Capsule(s)
Market status On market
Date entered into DSLD Oct 23, 2019
DSLD ID 207743
Product type Botanical
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Vegetarian, Adult (18 - 50 Years), Gluten Free, Dairy Free
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 Trans-Resveratrol by Vitacost, 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 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
Servings per container
60
UPC/BARCODE
844197012688
IngredientAmount% DV
Japanese Knotweed500 mg--

Other ingredients: Hydroxypropyl Methylcellulose, Rice Flour

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.
Formula

500 mg of herbal extract yielding 250 mg resveratrol

What is Resveratrol? Resveratrol, a substance found in grape skins and seeds and red wine, is an antioxidant polyphenol. Resveratrol is produced by many plants in response to environmental stressors such as drought, UV radiation from sunlight and fungal infections.

As an antioxidant, resveratrol works at the cellular level to protect healthy cells from free radical damage. Scientific evidence indicates that resveratrol is responsible for the cardioprotective properties of red wine.

Trans-resveratrol, the biologically active form of resveratrol, is the most studied resveratrol isomer.

Vitacost Trans-Resveratrol is a targeted wellness solution - just for you. Trans-resveratrol is the biologically active form of resveratrol. Provides 500 mg of resveratrol (standardized to 50% trans-resveratrol) per 1-capsule serving.

FDA Statement of Identity

Dietary Supplement

Precautions

Warnings Pregnant or lactating women, those with diabetes, hypoglycemics and people with known medical conditions and/or taking drugs should consult with a licensed physician and/or pharmacist prior to taking dietary supplements.

Formulation

Free of Milk, eggs, peanuts, tree nuts, crustacean shellfish, fish, soy, gluten, titanium dioxide.

Suitable for vegetarians.

Suggested/Recommended/Usage/Directions

Directions As a dietary supplement, take 1 capsule daily with food or as directed by a healthcare professional.

Storage

Keep dry and at room temperature (59(0)-86(0)F [15(0)-30(0)C]).

General Statements

What are the key benefits of Vitacost Trans-Resveratrol? A natural antioxidant for cardiovascular health.

About Vitacost Brand The search is over. Vitacost Brand supplements are focused on helping you create a strong foundation with simple, transparent formulas that support - and easily fit into - your daily life. Whether it's Everyday Essentials you're looking for or Targeted Wellness support, Vitacost Brand supplements offer the high-quality solution you need at the value price you deserve. We continuously look for ways to improve technology, processes and ingredients, so you feel confident about what you're putting in your body or giving your family. And it's all right here, at Vitacost.com

Standardization ensures consistent levels of active ingredients in each dose. Each bottle contains 60 servings. Provides the benefits of red wine without the alcohol and sugar.

Please note: The appearance of this product has changed. The capsules are now clear, not green. The active ingredients in the formula remain the same.

Potency Purity Pride All Vitacost supplements are formulated to deliver the level of support you expect and deserve. Whether you're shopping Vitacost vitamins, minerals, herbs or other key nutrients, their potency is guaranteed - what's on the label is what's in the bottle. Plus, all Vitacost supplements adhere to the FDA's Current Good Manufacturing Practices (CGMPs), ensuring that they are manufactured to high standards of potency, purity, efficacy and safety. We take pride in what we do, which is why we promise if you don't love your product, we'll take it back - even if the bottle is empty.

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.

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Trans-Resveratrol by Vitacost label

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

Trans-Resveratrol label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Trans-Resveratrol by Vitacost

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule Servings per container60 Amounts shown are per serving.

Japanese Knotweed

Interacts with
826 drugs
500 mg per serving Form: Trans-Resveratrol

Hu Zhang (Japanese knotweed root) is a traditional Chinese herb that is one of the richest natural sources of resveratrol and emodin. Some lab and ear...

Japanese Knotweed monograph & interactions

Other (inactive) ingredients: Hydroxypropyl Methylcellulose, Rice Flour. These complete the product’s ingredient list but are not active constituents.

Interaction report

Trans-Resveratrol by Vitacost Drug Interactions

Want to check YOUR meds against Trans-Resveratrol?

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
826Drugs
826 Moderate

Ingredients driving the most interactions

Japanese Knotweed 826

Individual Drug Interactions

The ingredients in Trans-Resveratrol interact with 826 drugs. Click any drug to see the details.

1 of the 1 ingredient in Trans-Resveratrol interact with drugs. Each result below shows which ingredient is responsible. Japanese Knotweed

Each ingredient & the kinds of drugs it affects

For each ingredient in Trans-Resveratrol with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

Japanese Knotweed7 drug types · 826 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, hu zhang might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs.
Hu zhang contains the constituent resveratrol. Resveratrol seems to have antiplatelet effects.

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

Theoretically, hu zhang might increase levels of drugs metabolized by CYP1A2.
Hu zhang contains the constituent resveratrol. In vitro research shows that resveratrol might inhibit the CYP1A2 enzyme. This interaction has not been reported in humans.

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

Theoretically, hu zhang might increase levels of drugs metabolized by CYP2C19.
Hu zhang contains the constituent resveratrol. In vitro research shows that resveratrol might inhibit the CYP2C19 enzyme. This interaction has not been reported in humans.

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

Theoretically, hu zhang might increase levels of drugs metabolized by CYP2E1.
Hu zhang contains the constituent resveratrol. In vitro research shows that resveratrol might inhibit the CYP2E1 enzyme. 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 Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, hu zhang might increase levels of drugs metabolized by CYP3A4.
Hu zhang contains the constituent resveratrol. In vitro research shows that resveratrol might inhibit the CYP3A4 enzyme. However, a clinical study in adults with NAFLD found that adding resveratrol 3000 mg daily for 8 weeks did not necessitate dose adjustments to any established medications metabolized by CYP3A4.

Likelihood Possible Evidence D
Estrogens

Theoretically, hu zhang might competitively inhibit the effects of estrogen replacement therapy.
In vitro research shows that hu zhang might have estrogenic activity.

Likelihood Possible Evidence D
Carbamazepine (Tegretol)

Theoretically, hu zhang might increase the effects and adverse effects of carbamazepine.
In animals, blood and tissue levels of carbamazepine were increased when given in combination with hu zhang. It is thought that increased levels of carbamazepine are due to cytochrome P450 3A4 (CYP3A4) inhibition. This interaction has not been reported in humans.

Likelihood Possible Evidence D
Japanese Knotweed full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Trans-Resveratrol, from the product label.

Vitacost

See all Vitacost products
Name
Vitacost
Web Address
www.vitacost.com
Pharmacist Counseling Corner

Trans-Resveratrol by Vitacost: Common Questions

Does Trans-Resveratrol by Vitacost interact with any medications?
Yes. Based on its ingredients, Trans-Resveratrol has a known interaction with 826 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Trans-Resveratrol contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism 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.
Is Japanese Knotweed safe to take while I'm pregnant?
There isn't enough safety data to know either way. Some compounds in knotweed may affect the uterus, so talk with your doctor or pharmacist to decide if it's right for you before taking it.
Can I take this if I'm breastfeeding?
No — there's not enough safety information available, and some compounds in knotweed may affect the bowel. It's best avoided while nursing unless you've discussed it with your doctor.
Will Japanese Knotweed help with my arthritis?
The evidence we have isn't strong enough to say whether it works for rheumatoid arthritis or osteoarthritis. Talk to your pharmacist about what the research actually shows.
What side effects might I experience?
The main concern is digestive upset from emodin, a compound in the knotweed. Human safety data for this supplement are limited overall.
What does resveratrol do?
Resveratrol is the active compound in Japanese Knotweed in this product. In lab studies, it shows enzyme-inhibiting and antiplatelet effects, which is why it interacts with certain medications.

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.

Trans-Resveratrol label
Go deeper

The Full Monographs Behind Trans-Resveratrol’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Hu Zhang

Interacts with 826 drugs

Hu Zhang (Japanese knotweed root) is a traditional Chinese herb that is one of the richest natural sources of resveratrol and emodin. Some lab and early human research looks interesting for...

Read the full Hu Zhang monograph →
Sources

Sources & How We Checked

Trans-Resveratrol'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 19 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.

Hu Zhang 19 references
  1. Pace-Asciak CR, Rounova O, Hahn SE, et al. Wines and grape juices as modulators of platelet aggregation in healthy human subjects. Clin Chim Acta 1996;246:163-82. PubMed
  2. Bertelli AA, Giovannini L, Bernini W, et al. Antiplatelet activity of cis-resveratrol. Drugs Exp Clin Res 1996;22:61-3.
  3. Pace-Asciak CR, Hahn S, Diamandis EP, et al. The red wine phenolics trans-resveratrol and quercetin block human platelet aggregation and eicosanoid synthesis: implications for protection against coronary heart disease. Clin Chim Acta 1995;235:207-19.
  4. Bertelli A, Bertelli AA, Gozzini A, Giovannini L. Plasma and tissue resveratrol concentrations and pharmacological activity. Drugs Exp Clin Res 1998;24:133-8.
  5. Bertelli AA, Giovannini L, Giannessi D, et al. Antiplatelet activity of synthetic and natural resveratrol in red wine. Int J Tissue React 1995;17:1-3.
  6. Piver B, Berthou F, Dreano Y, Lucas D. Inhibition of CYP3A, CYP1A and CYP2E1 activities by resveratrol and other non volatile red wine components. Toxicol Lett 2001;125:83-91. PubMed
  7. Matsuda H, Shimoda H, Morikawa T, Yoshikawa M. Phytoestrogens from the roots of Polygonum cuspidatum (Polygonaceae): structure-requirement of hydroxyanthraquinones for estrogenic activity. Bioorg Med Chem Lett 2001;11:1839-42. PubMed
  8. Zhang CZ, Wang SX, Zhang Y, et al. In vitro estrogenic activities of Chinese medicinal plants traditionally used for the management of menopausal symptoms. J Ethnopharmacol 2005;98:295-300. PubMed
  9. Chang, T. K., Chen, J., and Lee, W. B. Differential inhibition and inactivation of human CYP1 enzymes by trans-resveratrol: evidence for mechanism-based inactivation of CYP1A2. J.Pharmacol.Exp.Ther. 2001;299(3):874-882.
  10. Dobrydneva, Y., Williams, R. L., and Blackmore, P. F. trans-Resveratrol inhibits calcium influx in thrombin-stimulated human platelets. Br.J.Pharmacol. 1999;128(1):149-157.
  11. Kirk, R. I., Deitch, J. A., Wu, J. M., and Lerea, K. M. Resveratrol decreases early signaling events in washed platelets but has little effect on platalet in whole food. Blood Cells Mol.Dis. 2000;26(2):144-150.
  12. Zbikowska, H. M. and Olas, B. Antioxidants with carcinostatic activity (resveratrol, vitamin E and selenium) in modulation of blood platelet adhesion. J Physiol Pharmacol. 2000;51(3):513-520.
  13. Olas, B., Wachowicz, B., Saluk-Juszczak, J., and Zielinski, T. Effect of resveratrol, a natural polyphenolic compound, on platelet activation induced by endotoxin or thrombin. Thromb.Res 8-15-2002;107(3-4):141-145. PubMed
  14. Yu, C., Shin, Y. G., Kosmeder, J. W., Pezzuto, J. M., and van Breemen, R. B. Liquid chromatography/tandem mass spectrometric determination of inhibition of human cytochrome P450 isozymes by resveratrol and resveratrol-3-sulfate. Rapid Commun.Mass Spectro PubMed
  15. Ma, Z. H. and Ma, Q. Y. Resveratrol: a medical drug for acute pancreatitis. World J Gastroenterol. 6-7-2005;11(21):3171-3174. PubMed
  16. Pendurthi, U. R., Williams, J. T., and Rao, L. V. Resveratrol, a polyphenolic compound found in wine, inhibits tissue factor expression in vascular cells : A possible mechanism for the cardiovascular benefits associated with moderate consumption of wine. PubMed
  17. Chachay VS, Macdonald GA, Martin JH, Whitehead JP, O'Moore-Sullivan TM, Lee P, Franklin M, Klein K, Taylor PJ, Ferguson M, Coombes JS, Thomas GP, Cowin GJ, Kirkpatrick CM, Prins JB, Hickman IJ. Resveratrol does not benefit patients with nonalcoholic fatty
  18. Bedada SK, Neerati P. Resveratrol Pretreatment Affects CYP2E1 Activity of Chlorzoxazone in Healthy Human Volunteers. Phytother Res. 2016;30(3):463-8. PubMed
  19. Chi YC, Lin SP, Hou YC. A new herb-drug interaction of Polygonum cuspidatum, a resveratrol-rich nutraceutical, with carbamazepine in rats. Toxicol Appl Pharmacol 2012;263(3):315-22. PubMed

See these in context on the Hu Zhang monograph →

Parts of this content are provided by the Therapeutic Research Center, LLC.

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.

© 2021 Therapeutic Research Center, LLC

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