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, PhDCiteEditorial
📰Read the full Horny Goat Weed evidence review on GMJ News →Complete clinical article, references and updates on news.gmj.ge. This page is the structured safety summary.
3
Limited
Horny Goat Weed
Epimedium spp. (icariin)
Limited EvidenceLimitedBotanicals
RDA
Typical 250–1,000 mg
Target
N/A
Upper limit
No UL
Products
15
Dosage by population group — reference
✅ USP Verified, ConsumerLab Approved, Clean Label Project Certified
⚠ See overview for critical safety points [1]
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
Horny goat weed (icariin) is a genuine PDE5 inhibitor — same target as Viagra but ~80× weaker. The pharmacology is real; the clinical evidence is weak (small, low-quality studies). Patients using it for ED should understand: it's a weak PDE5 inhibitor, not a Viagra equivalent. The PDE5 interaction with nitrates applies (theoretical). Bone health (osteoblast stimulation) is an interesting secondary finding [1].
1 How much do I need?
👤 Adults: Specific dosage data under clinical review
👴 Elderly: Specific dosage data under clinical review
🤰 Pregnancy: See guidance
Avoid — PDE5 inhibition + hormonal effects [1].
👦 Pediatric: See guidance
Not recommended without specialist guidance [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: See overview [1].
💊 With food: See overview [1].
🚫 Avoid: See overview for contraindications [1].
2 Which form?
FormBioavailabilityVeganCost
['Various commercial forms', 'standard', 'See product labels [1].']StandardCheck label
3 Common questions
Key clinical point
Horny goat weed (icariin) is a genuine PDE5 inhibitor — same target as Viagra but ~80× weaker. The pharmacology is real; the clinical evidence is weak (small, low-quality studies). Patients using it for ED should understand: it's a weak PDE5 inhibitor, not a Viagra equivalent. The PDE5 interaction with nitrates applies (theoretical). Bone health (osteoblast stimulation) is an interesting secondary finding [1].
4 Clinical evidence

Strong

See overview [1]. HIGH

Moderate

See overview [1]. MODERATE

Insufficient

See overview [1]. LOW
5 Safety, toxicity & adverse events

Absolute contraindications

✕ Concurrent nitrates — icariin has PDE-5-inhibitory activity (additive hypotension risk)

Relative

⚠ Cardiovascular disease
⚠ Anticoagulants/antiplatelets — bleeding risk
⚠ Hormone-sensitive conditions
⚠ Documented adulteration with hidden PDE-5 drugs — sourcing concern

🚩 Red flags

See overview for safety alerts [1]
6 Interactions

Drug interactions

PDE5 inhibitors (sildenafil) Major
Mechanism: SAME target — additive vasodilation. Do NOT combine with Viagra/Cialis [1].
7 Regulatory
United States (FDA): Dietary supplement / restricted [1].
8 US supplement products
15
on-market products containing Horny Goat Weed (NIH DSLD)

Brands carrying Horny Goat Weed (15)

Click a brand to see its Horny Goat Weed products.
Or browse all 15 products in one list →
9 Frequently paired with
Maca 10 sharedSilicon 8 sharedTribulus 7 sharedMagnesium 6 shared
10 Cite this page
Vancouver: Pkhakadze G. Horny Goat Weed — safety profile [Internet]. Tbilisi: PHIG; 2026 [cited 2026 Jul 17]. Available from: https://supplement.ge/ingredients/horny-goat-weed/
APA 7th: Pkhakadze, G. (2026). Horny Goat Weed — Safety profile. Public Health Institute of Georgia. https://supplement.ge/ingredients/horny-goat-weed/
📋 Editorial information
Author: Prof. G. Pkhakadze, MD, MPH, PhD
Affiliation: David Tvildiani Medical University (DTMU)
First published: January 2026
Last reviewed: 2026-05-29
Next review: January 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. "Horny Goat Weed — Safety Profile." SupplementIndex, PHIG, 2026. https://supplement.ge/ingredients/horny-goat-weed/ 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
Educational and public health purposes. CC BY 4.0. Consult your healthcare provider before starting any supplement. Corrections: info@accreditation.ge. Publisher: PHIG