Grape Seed Extract — Safety Profile

Pkhakadze, Giorgi

✓ No active regulatory warningsFDA MedWatch, EMA EudraVigilance, WHO VigiBase, WADA Prohibited List · 2026-05-29

Updated: 2026-05-29 · v2.0 · Prof. G. Pkhakadze, MD, MPH, PhDCite Editorial

📰Read the full Grape Seed Extract evidence review on GMJ News →Complete clinical article, references and updates on news.gmj.ge. This page is the structured safety summary.

1

Safe

Grape Seed Extract

Vitis vinifera (OPC)

Generally SafeModerateBotanicals

RDA

Typical 100–300 mg

Target

Reduction

Upper limit

No UL

Products

36

Dosage by population group — reference

🔗 Best with: Vitamin C, Resveratrol, Pine Bark (Pycnogenol)✅ USP Verified, ConsumerLab Approved, Clean Label Project Certified

⚠ Similar to Pycnogenol but cheaper [1]

⚠ Antiplatelet — monitor with anticoagulants [1]

⚠ Modest BP effect [2]

ℹ️ Not obtained from food. Not applicable — this is not obtained from food in meaningful amounts; supplementation is the practical route.

🔬 Lab interpreter

ℹ️ No validated blood test. There is no established laboratory test to assess status or guide dosing for this ingredient. Clinical response and symptoms are the practical guide.

⚕ For professionals — confirm ranges against your local laboratory.

Clinical verdict

GSE provides OPCs — vasoprotective antioxidant polyphenols. Modest BP reduction in meta-analysis. Reduces leg edema from sitting/travel. Cheaper than Pycnogenol (similar OPCs). 100–300 mg/day [1] [2].

1 How much do I need?

👤 Adults: Specific dosage data under clinical review

👴 Elderly: Specific dosage data under clinical review

🤰 Pregnancy: See guidance

Limited data [1].

👦 Pediatric: See guidance

No data [1].

🏃 Athletes: Standard dose

⚖️ Obesity: Standard dose

Fat-soluble compounds may require dose adjustment in obesity.

🩺 Renal: Consult specialist

Dose adjustment may be needed in renal impairment.

🌱 Vegan: Standard dose

How to take

🍽 Timing: With meals [1].

💊 With food: With food [1].

🚫 Avoid: Anticoagulants without monitoring [1].

2 Which form?

Form	Bioavailability	Vegan	Cost
['GSE standardized to 95% OPCs', 'preferred', '100–300 mg/day [2].']	Standard	Check label

3 Common questions

GSE vs Pycnogenol? ▼

Both provide OPCs from different sources. Pycnogenol has more clinical trials (it's patented and funded more research). GSE is cheaper. Similar mechanisms [1].

4 Clinical evidence

Strong

OPC antioxidant and vasoprotective activity: well-characterized [1]. HIGH

Moderate

BP: meta-analysis — modest reduction [2]. Edema: reduced leg swelling in travel/sitting studies [1]. Venous insufficiency: improved symptoms [1]. MODERATE

Insufficient

Cancer prevention [1]. Cognitive function [1]. Diabetes [1]. LOW

5 Safety, toxicity & adverse events

Relative

⚠ Anticoagulants/antiplatelets — bleeding risk; discontinue before surgery

⚠ Antihypertensives — additive effect

⚠ May affect CYP-metabolized drugs at high doses

🚩 Red flags

● Anticoagulant patient [1]

6 Interactions

Drug interactions

Anticoagulants Minor

Mechanism: Mild antiplatelet from OPCs. [1]

Effect: Theoretical bleeding. [1]

Action: Monitor [1].

Supplement synergies

Vitamin C · 500 mg
Synergistic antioxidant [1].

7 Regulatory

United States: Dietary supplement [1].

France: Masquelier's OPC is a pharmaceutical product [1].

8 US supplement products

36

on-market products containing Grape Seed Extract (NIH DSLD)

Brands carrying Grape Seed Extract (3)

Click a brand to see its Grape Seed Extract products.

Or browse all 36 products in one list →

9 Frequently paired with

Vitamin C 15 shared Calcium 12 shared Iodine 10 shared Niacin 10 shared Vitamin E 10 shared Vitamin A 9 shared Riboflavin 9 shared Selenium 9 shared

Grape Seed Extract vs Vitamin C Grape Seed Extract vs Resveratrol

10 Cite this page

Vancouver: Pkhakadze G. Grape Seed Extract — safety profile [Internet]. Tbilisi: PHIG; 2026 [cited 2026 Aug 31]. Available from: https://supplement.ge/ingredients/grape-seed-extract/

APA 7th: Pkhakadze, G. (2026). Grape Seed Extract — Safety profile. Public Health Institute of Georgia. https://supplement.ge/ingredients/grape-seed-extract/

📋 Editorial information

Author: Prof. G. Pkhakadze, MD, MPH, PhD

Institution: Public Health Institute of Georgia (PHIG)

Affiliation: David Tvildiani Medical University (DTMU)

First published: January 2026

Last reviewed: 2026-05-29

Next review: March 2027

References: 2 cited sources

COI: SupplementIndex receives no funding from supplement manufacturers. All content independently authored by PHIG.

Process: Systematic literature review

📄 License & reuse

Published under Creative Commons Attribution 4.0 International (CC BY 4.0). You may share and adapt for any purpose with attribution.

Pkhakadze G. "Grape Seed Extract — Safety Profile." SupplementIndex, PHIG, 2026. https://supplement.ge/ingredients/grape-seed-extract/ CC BY 4.0.

GP

Prof. G. Pkhakadze, MD, MPH, PhD

Professor of Public Health · Head of Department, DTMU

Editor-in-Chief, Georgian Medical Journal (ISSN 3088-4322)

Chair, Public Health Institute of Georgia · UEMS Public Health Section

🏛 PHIG 📰 GMJ 🆔 ORCID

Educational and public health purposes. CC BY 4.0. Consult your healthcare provider before starting any supplement. Corrections: info@accreditation.ge. Publisher: PHIG