Horny goat weed,
does it really help with Improvement of erectile function and libido?
research showsA single-dose human pharmacokinetic and tolerability study of standardized Epimedium extract exists, but no human efficacy trial of Epimedium or icariin alone was found that assessed IIEF in patients with erectile dysfunction or measured libido. Erectile evidence centers on cell and animal experiments, so the efficacy grade is ?.
ads claimAdvertisements use phrases such as 'natural Viagra,' 'PDE5 inhibition,' and 'raises male vitality and libido.' A laboratory PDE5 mechanism is not a clinical result establishing improved IIEF or libido in humans.
Useful facts when choosing a product
- Icariin and prenylflavonoid content varies across Epimedium species and extracts.
- The human single-dose study used 370-1,110 mg of extract, but it was not a dose-finding efficacy trial.
- A single dose was tolerated in healthy men, while repeated-use safety data remain limited.
- Results from multi-ingredient male products cannot be attributed to Epimedium or icariin alone.
Chamgap Semantic Classification Code
Candidate index · review held
S.horny-goat-weed.UNK.erectile-function-and-libido.improve.placeboSupplements and nutraceuticals > Horny goat weed > Unknown > erectile function and libido > Improvement claim > Placebo
An automated migration candidate, not an issued permanent code; exact claim scope remains under review. This machine-generated migration candidate helps retrieval but is not a permanent assignment. The original verdict ID and URL remain authoritative.
What the research actually shows
Shindel 2010 reported erectile-related signals after icariin exposure in cells and rats, not a human efficacy trial. Teo 2019 gave single doses of 370, 740, or 1,110 mg standardized Epimedium extract to 30 healthy men and measured metabolites and 48-hour tolerability, with no erectile-function or libido endpoint. The Niu 2022 review likewise centered on pharmacokinetics, molecular mechanisms, and preclinical data rather than clinical efficacy.
Why this is classified as ?
No standalone human efficacy trial directly assessing erectile function or libido was found. Preclinical mechanisms and human pharmacokinetics do not substitute for efficacy literature, so the grade is ? with a null score.
Counterpoint. Absorbable metabolites and preclinical activity have been shown and leave open a rationale for future trials. This judgment means absence of efficacy literature, not proof of no effect.
Rejudgment record. New judgment — There is no standalone human efficacy trial directly measuring erectile function or libido for Epimedium or icariin; identified human research is a single-dose pharmacokinetic and tolerability study
Cross-check — AI research and Codex final gate
Evidence Table
| Study | Design | Sample | Funding | Endpoint | Result | Weight |
|---|---|---|---|---|---|---|
| Shindel AW et al. 2010 | Cell and rat preclinical study | Unknown | Cavernous nerve, smooth muscle, and erectile response in rats | Reported preclinical erectile-related signals but provided no human symptom or IIEF data. | Not used for grade | |
| Teo YL et al. 2019 | Randomized placebo-controlled single-dose pharmacokinetic study | 30 | Singapore academic/public institutions; details unclear | Prenylflavonoid pharmacokinetics and 48-hour tolerability | Icariside II and other metabolites were detected and a single dose was tolerated, but sexual-function efficacy was not measured. | Not used for efficacy grade |
Receipt — 3 References
All 3 cited sources were verified for existence at the original page (as of 2026-07-11).
Final verification and publication gate: Codex · Evidence date: 2026-07-11 · Corrections: none
Cite this verdict
[Chamgap] Horny goat weed (Epimedium species, icariin) x improvement of erectile function and libido — Evidence Grade ?. 3 cited sources checked. Source: https://chamgap.com/en/verdicts/mens/epimedium-icariin-erection-libido/ · CC BY 4.0CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.
What this document does and does not do
Chamgap is an information source. It reports what research has and has not confirmed; it does not tell readers what to take or buy. That decision belongs to readers and, when needed, medical or legal professionals. This verdict reflects literature available up to the search date and may change as new research appears. Nothing here is medical advice.