Clinical OPC Ingredients & Drug Interactions
by EuroMedica
What is this page for?
First and foremost: checking Clinical OPC 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
Clinical OPC is a dietary supplement by EuroMedica with 1 active ingredient. Its ingredients are commonly taken for antioxidant support, heart and circulation health, vein problems (such as varicose veins).Based on those ingredients, 910 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are French Grape (Vitis vinifera L.) seed extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against Clinical OPC by EuroMedica
Ask about any prescription or over-the-counter medication and we check it for interactions with Clinical OPC by EuroMedica — and tell you which ingredient is responsible.
AI summaries are generated from our interaction database for education only — always confirm with your pharmacist. How we use AI
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HelloPharmacist Scorecard of Clinical OPC by EuroMedica
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.
What’s inside
Full disclosure
Clinical OPC is a single-ingredient supplement: French grape (Vitis vinifera L.) seed extract, which is a concentrated source of oligomeric proanthocyanidins — compounds called OPCs that give grapes their antioxidant power. The capsule also contains inactive ingredients (cellulose powder, hydroxypropyl methylcellulose, silicon dioxide, and vegetable-source magnesium stearate) that help form and stabilize the capsule.
Does it work?
Moderate evidence
The evidence for grape seed extract centers on chronic venous insufficiency (CVI) — a condition where veins in the legs have trouble returning blood to the heart — and for that use it's rated possibly effective. For chemotherapy-related nausea and vomiting, allergic rhinitis (hay fever), and weight loss, the evidence is rated possibly ineffective, meaning the studies don't show meaningful benefit.
How safe is it?
Well-documented data
Grape seed extract is generally well tolerated, with most people experiencing no problems. The most common side effects are mild: abdominal pain, diarrhea, dry mouth, indigestion, headache, joint pain, and nausea.
Rarely, anaphylaxis to grape skin has been reported. For pregnancy, concentrated grape supplements are best avoided due to limited safety data; whole grapes as food are fine.
For breastfeeding, there isn't enough information on concentrated supplements to say either way, so talk with your doctor or pharmacist about whether this product fits your situation.
Meds to double-check
Moderate interaction found
Before you take Clinical OPC, double-check your medications — especially blood thinners and antiplatelet drugs (warfarin, aspirin, clopidogrel), immunosuppressants like cyclosporine, sedatives like midazolam, and any drugs processed by your liver's CYP2D6, CYP3A4, CYP2E1, or CYP1A2 systems. If you're unsure whether your medications fall into these categories, use the interaction checker on this page or ask your pharmacist.
The bottom line
Scorecard at a glanceFully disclosed formula with some supporting evidence for its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.
If you have chronic venous insufficiency and are looking for a possibly effective option, this product may be worth discussing with your healthcare provider. However, if you take a blood thinner, an immunosuppressant, a sedative, or any other regular medication, you'll want to check your exact drugs first — grape seed extract can affect how several medications work.
Talk with your doctor or pharmacist before starting to make sure it's right for you.
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 22, 2015.
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
General information
Key facts about Clinical OPC, straight from the product label.
| Brand | EuroMedica |
|---|---|
| Barcode (UPC) | 367703836061 |
| Net contents | 60 Capsule(s) |
| Market status | On market |
| Date entered into DSLD | Oct 22, 2015 |
| DSLD ID | 52923 |
| Product type | Botanical |
| Supplement form | Capsule |
| Dietary claims / uses | All Other, Structure/Function |
| Intended target group(s) | Vegan, Vegetarian, Adult (18 - 50 Years), Gluten Free, Dairy Free, Sugar Free |
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 Clinical OPC by EuroMedica, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| French Grape (Vitis vinifera L.) seed extract | 150 mg | -- |
Other ingredients: Cellulose powder, Hydroxypropyl Methylcellulose, Silicon Dioxide, Vegetable Source Magnesium Stearate
Tap any ingredient to jump to its full detail below.
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.
General Statements
Oligomeric Proanthocyanidins (OPCs) are the clinically proven health promoting nutrients in grape seed extract. Other grape seed extracts may contain tannins, which are large, poorly absorbed molecules counted as OPCs.
Already within normal range In conjunction with a healthy diet and exercise plan
Suggested/Recommended/Usage/Directions
Recommendations: 1 capsule daily, or as recommended by your healthcare professional.
Precautions
If pregnant or nursing, consult a healthcare practitioner before use.
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.
General
JC 34 91 + 3(5,6)EP L83606.02
Formulation
High Absorption – Tannin Free Grape Seed Extract
No sugar, salt, yeast, wheat, gluten, corn, soy, dairy products, artificial coloring, artificial flavoring, or artificial preservatives. NON-GMO
Formula
High Absorption – Tannin Free Grape Seed Extract
FDA Statement of Identity
Dietary Supplement
Seals/Symbols
V VEGAN
Brand IP Statement(s)
Clinical OPC is tannin free and supports healthy: - Heart and Arteries - Blood Sugar - Cellular Protection and Immune Function - Weight Management - Focus and Concentration - Blood Pressure and Cholesterol Balance*
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
Clinical OPC by EuroMedica label
The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.
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)The Ingredients in Clinical OPC by EuroMedica
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.
French Grape (Vitis vinifera L.) seed extract
Interacts with910 drugs
Grapes and grape products like grape seed extract contain antioxidant compounds such as resveratrol and proanthocyanidins that may support heart and b...
French Grape (Vitis vinifera L.) seed extract monograph & interactionsOther (inactive) ingredients: Cellulose powder, Hydroxypropyl Methylcellulose, Silicon Dioxide, Vegetable Source Magnesium Stearate. These complete the product’s ingredient list but are not active constituents.
Clinical OPC by EuroMedica Drug Interactions
HelloPharmacist Interaction Report
Clinical OPC by EuroMedica contains French grape seed extract, which has documented interactions with several medication types.
The most serious concern is with blood thinners and antiplatelet drugs (like warfarin or aspirin) — grape extract may have mild blood-thinning effects itself and could theoretically increase your bleeding risk if combined with these medications.
Read the full breakdown — every affected drug type, severity by severity
Grape seed extract may also affect how your body processes a number of other medications through the liver enzyme systems CYP2D6, CYP3A4, CYP2E1, and CYP1A2. The research here is mixed — some suggests it could raise drug levels, others suggest it might lower them — but human studies are limited.
Specific known concerns include cyclosporine (an immunosuppressant), where grape juice has been shown to reduce absorption by up to 30%, and midazolam (a sedative), where long-term grape seed extract might decrease its effects. There's also a small study showing grape juice can lower levels of phenacetin, an older pain reliever.
Additionally, we could not find specific human evidence confirming that these interactions occur at the doses used in supplements, though the lab and animal research warrants caution. Altogether, these interactions span 911 individual medications.
Before you start this product, especially if you take a blood thinner, an immunosuppressant, a sedative, or any regular prescription medication, run your exact drugs through the interaction checker on this page or talk with your pharmacist.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against Clinical OPC?
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 checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in Clinical OPC interact with 910 drugs. Click any drug to see the details.
1 of the 1 ingredient in Clinical OPC interact with drugs. Each result below shows which ingredient is responsible. French Grape (Vitis vinifera L.) seed extract
Ado-trastuzumab EmtansineKadcyla
How Ado-trastuzumab Emtansine interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
It is unclear if grape seed extract inhibits or induces CYP3A4; research is conflicting.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Ado-trastuzumab Emtansine interactionAbciximabReoPro
How Abciximab interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, grape extracts may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Abciximab interactionAbemaciclibVerzenio
How Abemaciclib interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
It is unclear if grape seed extract inhibits or induces CYP3A4; research is conflicting.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Abemaciclib interactionAbiraterone
How Abiraterone interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
It is unclear if grape seed extract inhibits or induces CYP3A4; research is conflicting.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Abiraterone interactionAbiraterone AcetateYonsa, Zytiga
How Abiraterone Acetate interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
It is unclear if grape seed extract inhibits or induces CYP3A4; research is conflicting.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Abiraterone Acetate interactionAbrocitinibCibinqo
How Abrocitinib interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 2c9 (cyp2c9) Substrates, Anticoagulant/antiplatelet Drugs Moderate
Interaction Summary
It is unclear if grape juice or grape seed extract inhibits CYP2C9; research is conflicting.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Abrocitinib interactionAcalabrutinibCalquence
How Acalabrutinib interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
It is unclear if grape seed extract inhibits or induces CYP3A4; research is conflicting.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acalabrutinib interactionAcenocoumarolSintrom
How Acenocoumarol interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractAnticoagulant/antiplatelet Drugs Moderate
Interaction Summary
Theoretically, grape extracts may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acenocoumarol interactionAcetaminophenChildren's Tylenol, Children's Tylenol Meltaways, Tylenol, Tylenol Ex Strength
How Acetaminophen interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 2e1 (cyp2e1) Substrates, Cytochrome P450 1a2 (cyp1a2) Substrates Moderate
Interaction Summary
Theoretically, grape seed extract might increase the levels of CYP2E1 substrates.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen interactionAcetaminophen, AspirinGemnisyn
How Acetaminophen, Aspirin interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 1a2 (cyp1a2) Substrates, Anticoagulant/antiplatelet Drugs +1 Moderate
Interaction Summary
Theoretically, grape juice might reduce the levels of CYP1A2 substrates.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen, Aspirin interactionAcetaminophen, Aspirin, CaffeineExcedrin, Excedrin Extra Strength, Excedrin Migraine
How Acetaminophen, Aspirin, Caffeine interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 2e1 (cyp2e1) Substrates, Anticoagulant/antiplatelet Drugs +2 Moderate
Interaction Summary
Theoretically, grape seed extract might increase the levels of CYP2E1 substrates.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen, Aspirin, Caffeine interactionAcetaminophen, Brompheniramine, PhenylpropanolamineDimetapp Cold and Flu
How Acetaminophen, Brompheniramine, Phenylpropanolamine interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 2e1 (cyp2e1) Substrates, Cytochrome P450 1a2 (cyp1a2) Substrates Moderate
Interaction Summary
Theoretically, grape seed extract might increase the levels of CYP2E1 substrates.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen, Brompheniramine, Phenylpropanolamine interactionAcetaminophen, ButalbitalAxocet, Bancap, Bucet, Butex Forte, Esgic CF, Orbivan CF +5 more
How Acetaminophen, Butalbital interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 2e1 (cyp2e1) Substrates Moderate
Interaction Summary
Theoretically, grape juice might reduce the levels of CYP1A2 substrates.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen, Butalbital interactionAcetaminophen, Butalbital, CaffeineEsgic, Esgic Plus, Fiogesic, Fioricet, Repan, Tecnal +1 more
How Acetaminophen, Butalbital, Caffeine interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 2e1 (cyp2e1) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates +1 Moderate
Interaction Summary
Theoretically, grape seed extract might increase the levels of CYP2E1 substrates.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen, Butalbital, Caffeine interactionAcetaminophen, Butalbital, Caffeine, CodeineEsgic with Codeine, Fioricet w/ Codeine
How Acetaminophen, Butalbital, Caffeine, Codeine interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 2e1 (cyp2e1) Substrates +2 Moderate
Interaction Summary
Theoretically, grape juice might reduce the levels of CYP1A2 substrates.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen, Butalbital, Caffeine, Codeine interactionAcetaminophen, Butalbital, CodeineBancap w/ Codeine
How Acetaminophen, Butalbital, Codeine interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 2e1 (cyp2e1) Substrates, Cytochrome P450 1a2 (cyp1a2) Substrates +1 Moderate
Interaction Summary
Theoretically, grape seed extract might increase the levels of CYP2E1 substrates.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen, Butalbital, Codeine interactionAcetaminophen, Butalbital, Codeine PhosphatePhrenilin #3
How Acetaminophen, Butalbital, Codeine Phosphate interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 2e1 (cyp2e1) Substrates +1 Moderate
Interaction Summary
Theoretically, grape juice might reduce the levels of CYP1A2 substrates.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen, Butalbital, Codeine Phosphate interactionAcetaminophen, Caffeine, Chlorpheniramine, Hydrocodone, PhenylephrineHycomine Compound
How Acetaminophen, Caffeine, Chlorpheniramine, Hydrocodone, Phenylephrine interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 2d6 (cyp2d6) Substrates +2 Moderate
Interaction Summary
Theoretically, grape juice might reduce the levels of CYP1A2 substrates.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen, Caffeine, Chlorpheniramine, Hydrocodone, Phenylephrine interactionAcetaminophen, Caffeine, CodeineGesic C15, Gesic C30, Gesic C8, Lenoltec 1, Lenoltec 2, Lenoltec 3 +1 more
How Acetaminophen, Caffeine, Codeine interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 2e1 (cyp2e1) Substrates, Cytochrome P450 1a2 (cyp1a2) Substrates +2 Moderate
Interaction Summary
Theoretically, grape seed extract might increase the levels of CYP2E1 substrates.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen, Caffeine, Codeine interactionAcetaminophen, Caffeine, Codeine, SalicylamideCodalan No.1, Codalan No.2, Codalan No.3
How Acetaminophen, Caffeine, Codeine, Salicylamide interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 3a4 (cyp3a4) Substrates, Cytochrome P450 2e1 (cyp2e1) Substrates +2 Moderate
Interaction Summary
It is unclear if grape seed extract inhibits or induces CYP3A4; research is conflicting.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen, Caffeine, Codeine, Salicylamide interactionAcetaminophen, Caffeine, DihydrocodeineDHC Plus, Panlor DC, Panlor SS
How Acetaminophen, Caffeine, Dihydrocodeine interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 2d6 (cyp2d6) Substrates +2 Moderate
Interaction Summary
Theoretically, grape juice might reduce the levels of CYP1A2 substrates.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen, Caffeine, Dihydrocodeine interactionAcetaminophen, Caffeine, IsomethepteneMigralam
How Acetaminophen, Caffeine, Isometheptene interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 3a4 (cyp3a4) Substrates, Cytochrome P450 2e1 (cyp2e1) Substrates +1 Moderate
Interaction Summary
It is unclear if grape seed extract inhibits or induces CYP3A4; research is conflicting.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen, Caffeine, Isometheptene interactionAcetaminophen, Caffeine, PyrilamineMidol Max Strength Menstrual
How Acetaminophen, Caffeine, Pyrilamine interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 2e1 (cyp2e1) Substrates +1 Moderate
Interaction Summary
Theoretically, grape juice might reduce the levels of CYP1A2 substrates.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen, Caffeine, Pyrilamine interactionAcetaminophen, Chlorpheniramine Maleate, Dextromethorphan HbrVicks Formula 44M Cough, Cold & Flu Relief
How Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan Hbr interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 2e1 (cyp2e1) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates +2 Moderate
Interaction Summary
Theoretically, grape seed extract might increase the levels of CYP2E1 substrates.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan Hbr interactionAcetaminophen, Chlorpheniramine, Codeine, PhenylephrineColrex
How Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 3a4 (cyp3a4) Substrates, Cytochrome P450 2e1 (cyp2e1) Substrates +2 Moderate
Interaction Summary
It is unclear if grape seed extract inhibits or induces CYP3A4; research is conflicting.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine interactionAcetaminophen, Chlorpheniramine, DextromethorphanCoricidin II Extra Strength Cold and Flu
How Acetaminophen, Chlorpheniramine, Dextromethorphan interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates +2 Moderate
Interaction Summary
Theoretically, grape juice might reduce the levels of CYP1A2 substrates.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen, Chlorpheniramine, Dextromethorphan interactionAcetaminophen, Chlorpheniramine, Dextromethorphan HydrobromideCoricidin HBP Maximum Strength Flu
How Acetaminophen, Chlorpheniramine, Dextromethorphan Hydrobromide interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 2e1 (cyp2e1) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates +2 Moderate
Interaction Summary
Theoretically, grape seed extract might increase the levels of CYP2E1 substrates.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen, Chlorpheniramine, Dextromethorphan Hydrobromide interactionAcetaminophen, Chlorpheniramine, Dextromethorphan, PhenylpropanolamineMulti Symptom Cold Relief
How Acetaminophen, Chlorpheniramine, Dextromethorphan, Phenylpropanolamine interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 3a4 (cyp3a4) Substrates, Cytochrome P450 2e1 (cyp2e1) Substrates +2 Moderate
Interaction Summary
It is unclear if grape seed extract inhibits or induces CYP3A4; research is conflicting.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen, Chlorpheniramine, Dextromethorphan, Phenylpropanolamine interactionAcetaminophen, Chlorpheniramine, Dextromethorphan, PseudoephedrineChildren's Tylenol Cold Plus Cough, Tylenol Cold Ex Strength
How Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 2d6 (cyp2d6) Substrates +2 Moderate
Interaction Summary
Theoretically, grape juice might reduce the levels of CYP1A2 substrates.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine interactionAcetaminophen, Chlorpheniramine, Guaifenesin, Phenylephrine, SalicylamideRhinogesic GG
How Acetaminophen, Chlorpheniramine, Guaifenesin, Phenylephrine, Salicylamide interacts with Clinical OPC — through 1 ingredient. Tap an ingredient for the detail:
French Grape (vitis Vinifera L.) Seed ExtractCytochrome P450 2e1 (cyp2e1) Substrates, Cytochrome P450 1a2 (cyp1a2) Substrates +1 Moderate
Interaction Summary
Theoretically, grape seed extract might increase the levels of CYP2E1 substrates.
Read the full French Grape (vitis Vinifera L.) Seed Extract + Acetaminophen, Chlorpheniramine, Guaifenesin, Phenylephrine, Salicylamide interactionEach ingredient & the kinds of drugs it affects
For each ingredient in Clinical OPC 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.
French Grape (Vitis vinifera L.) seed extract
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.
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.
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.
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.
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.
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.
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.
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).
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.
Brand information
Manufacturer and brand details for Clinical OPC, from the product label.
EuroMedica
See all EuroMedica products- Name
- EuroMedica
- Street Address
- 955 Challenger Dr
- City
- Green Bay
- State
- WI
- ZipCode
- 54311
- Phone Number
- 866-842-7256
- Web Address
- EuroMedicaUSA.com
Clinical OPC by EuroMedica: Common Questions
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The Full Monographs Behind Clinical OPC’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Sources & How We Checked
Clinical OPC'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.
- NIH Dietary Supplement Label Database (DSLD) — The official product label on file for this supplement.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference behind the ingredient interaction data.
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 34 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.
Grape 34 references
- Kiesewetter H, Koscielny J, Kalus U, et al. Efficacy of orally administered extract of red vine leaf AS 195 (folia vitis viniferae) in chronic venous insufficiency (stages I-II). A randomized, double-blind, placebo-controlled trial. Arzneimittelforschung
- Xiao Dong S, Zhi Ping Z, Zhong Xiao W, et al. Possible enhancement of the first-pass metabolism of phenacetin by ingestion of grape juice in Chinese subjects. Br J Clin Pharmacol 1999;48:638-40. PubMed
- Vaswani SK, Hamilton RG, Carey RN, et al. Anaphylaxis recurrent urticaria and angioedema from grape hypersensitivity. J Allergy Clin Immunol 1998;101:S31.
- Chevallier A. The Encyclopedia of Medicinal Plants. London, UK: Dorling Kindersley, Ltd., 1996.
- Bernstein DI, Bernstein CK, Deng C, et al. Evaluation of the clinical efficacy and safety of grapeseed extract in the treatment of fall seasonal allergic rhinitis: a pilot study. Ann Allergy Asthma Immunol 2002;88:272-8.. PubMed
- Greenblatt DJ, von Moltke LL, Perloff ES, et al. Interaction of flurbiprofen with cranberry juice, grape juice, tea, and fluconazole: in vitro and clinical studies. Clin Pharmacol Ther 2006;79:125-33. PubMed
- Ward NC, Hodgson JM, Croft KD, et al. The combination of vitamin C and grape-seed polyphenols increases blood pressure: a randomized, double-blind, placebo-controlled trial. J Hypertens 2005;23:427-34.. PubMed
- Ray, S. D., Parikh, H., Hickey, E., Bagchi, M., and Bagchi, D. Differential effects of IH636 grape seed proanthocyanidin extract and a DNA repair modulator 4-aminobenzamide on liver microsomal cytochrome 4502E1-dependent aniline hydroxylation. Mol Cell B PubMed
- 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.
- 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
- 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
- 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
- Samet, J. M. and Coultas, D. B. Reduced forced vital capacity in California grape workers. What does it mean? Am Rev.Respir.Dis 1992;145(2 Pt 1):255-256. PubMed
- Gamsky, T. E., McCurdy, S. A., Samuels, S. J., and Schenker, M. B. Reduced FVC among California grape workers. Am Rev.Respir.Dis 1992;145(2 Pt 1):257-262. PubMed
- 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
- 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
- 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
- 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
- Oliveira-Freitas, V. L., Dalla, Costa T., Manfro, R. C., Cruz, L. B., and Schwartsmann, G. Influence of purple grape juice in cyclosporine bioavailability. J Ren Nutr. 2010;20(5):309-313. PubMed
- Hollis, J. H., Houchins, J. A., Blumberg, J. B., and Mattes, R. D. Effects of concord grape juice on appetite, diet, body weight, lipid profile, and antioxidant status of adults. J Am Coll.Nutr. 2009;28(5):574-582. PubMed
- Dohadwala, M. M., Hamburg, N. M., Holbrook, M., Kim, B. H., Duess, M. A., Levit, A., Titas, M., Chung, W. B., Vincent, F. B., Caiano, T. L., Frame, A. A., Keaney, J. F., Jr., and Vita, J. A. Effects of Concord grape juice on ambulatory blood pressure in
- Rabe, E., Stucker, M., Esperester, A., Schafer, E., and Ottillinger, B. Efficacy and tolerability of a red-vine-leaf extract in patients suffering from chronic venous insufficiency--results of a double-blind placebo-controlled study. Eur.J Vasc.Endovasc. PubMed
- Trotta, M., Cesaretti, M., Conzi, R., Derchi, L. E., and Borgonovo, G. Elderly male with mesogastric pain. Small bowel obstruction caused by an intact fresh grape. Ann.Emerg.Med 2011;58(4):e1-e2. PubMed
- McCurdy, S. A., Wiggins, P., Schenker, M. B., Munn, S., Shaieb, A. M., Weinbaum, Z., Goldsmith, D., McGillis, S. T., Berman, B., and Samuels, S. Assessing dermatitis in epidemiologic studies: occupational skin disease among California grape and tomato ha
- Winter, C. K. and Kurtz, P. H. Factors influencing grape worker susceptibility to skin rashes. Bull.Environ.Contam Toxicol. 1985;35(3):418-426. PubMed
- Yamasaki, R., Dekio, S., and Jidoi, J. Contact dermatitis from grape bud. Contact Dermatitis 1985;12(4):226-227. PubMed
- Cox, J. and Grigg, M. Small bowel obstruction by an intact grape. J Am Geriatr.Soc 1986;34(7):550. PubMed
- Faircloth, D. E. and Robison, W. J. Obstruction of the sigmoid colon by grape seeds. JAMA 11-27-1981;246(21):2430. PubMed
- Marguerie, C. and Drouet, M. [Occupational eosinophilic lung in a grape grower: role of sulfites]. Allerg.Immunol.(Paris) 1995;27(5):163-167.
- 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
- Ras RT, Zock PL, Zebregs YE, et al. Effect of polyphenol-rich grape seed extract on ambulatory blood pressure in subjects with pre- and stage I hypertension. Br J Nutr 2013;110(12):2234-41. PubMed
- Berry AC, Nakshabendi R, Abidali H, et al. Adverse effects of grape seed extract supplement: A clinical case and long-term follow-up. J Diet Suppl. 2016;13(2):232-5. PubMed
- Martínez-Maqueda D, Zapatera B, Gallego-Narbón A, Vaquero MP, Saura-Calixto F, Pérez-Jiménez J. A 6-week supplementation with grape pomace to subjects at cardiometabolic risk ameliorates insulin sensitivity, without affecting other metabolic syndrome mark
- 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
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