Compound or practice · Supplement
Horny Goat Weed
A libido herb whose active icariin is a weak PDE5 inhibitor in theory and essentially untested in humans.
- Overall grade
- Grade D
- Last revised
- 1
- graded outcome
- 0
- references listed
A structured monograph in Prometheus's bundled library. Its grades are the monograph's own reading of the evidence, not a peer-reviewed review.
1 at grade D — 1 graded row
What is known
Each outcome with its grade (how strong the evidence is, A to D), the size of the effect where the entry records one, and how often studies agree.
- Erectile function (humans)Evidence grade D
No real trials
Unclearlow
What is uncertain
Read off the same rows as above. Nothing here is added that the entry does not itself record.
- Thin evidence: Erectile function (humans) (grade D).
The evidence in words
What it is
Horny goat weed (Epimedium) contains icariin, marketed for erectile function and libido.
How it works
Icariin weakly inhibits PDE5 (the target of erectile-dysfunction drugs) in lab studies.
What the evidence shows
Despite the plausible mechanism, human trials are essentially absent; the icariin content of supplements is usually far too low to matter. Marketing well ahead of evidence.
How to use it
Not recommended given the lack of human data.
Safety & interactions
Limited data; possible cardiovascular effects at high doses.
Bottom line
A plausible mechanism with no real human evidence and typically sub-therapeutic dosing. Skip it for proven options.
How it is used
As the entry records it, from the studies it summarises. Not a recommendation for you — doses that suit a trial population may not suit you.
- n/a
- Not recommended.
Related reading
Entries that share this one's tags or conditions.
- Horny Goat Weed for Erectile function (humans)Evidence grade D — No real trialsEvidence grade D
- Horny Goat Weed: dosage and how to take itNot recommended.Evidence grade D
- Horny Goat Weed: side effects, safety & interactionsLimited data; possible cardiovascular effects at high doses.Evidence grade D
- Stinging NettleModest data for BPH urinary symptoms and allergic rhinitis; a benign multipurpose folk remedy.Evidence grade C
Sources
This entry lists no references of its own.
Last revised . A grade is this entry's reading of the evidence, not medical advice.