Quick Navigation

Horny Goat Weed

Epimedium, known as Horny Goat Weed, is an erectile aid and aphrodisiac used in Traditional Chinese Medicine that just so happens to also increase testosterone in research animals (has not been looked at in humans). May also be a cognitive booster and heart health agent.

Our evidence-based analysis on horny goat weed features 46 unique references to scientific papers.

Research analysis led by .
Reviewed by
Examine.com Team
Last Updated:

Summary of Horny Goat Weed

Primary information, health benefits, side effects, usage, and other important details

Horny Goat Weed is a herb (Epimedium) that is known for being an aphrodisiac and touted as a Testosterone Booster. It derives its layman names from goats and sheep who acted a bit more frisky after consuming Epimedium that grew near their fields.

It is also sometimes referred to by its active ingredient, Icariin. Icariin is known as a prenylated flavonoid compound and has been shown to exert much of the aphrodisiac effects of Horny Goat Weed. It has also been shown in one rat study to increase testosterone levels at a rather high dose, and moderate dosages are shown to be beneficial for bone health.

Icariin has not been shown to increase testosterone in females, yet two other compounds in Horny Goat Weed (Icaritin, Desmethylicaritin) have actually increased estrogen in post-menopausal females. The herb acts as an aphrodisiac in both genders, and the gender-specific hormone increasing could be beneficial for both genders.

Make sure you only take supplements that work

Examine.com bases all of its recommendations on published scientific research. We’re a trusted resource because we don’t sell or even advertise supplements.

If you’re tired of wasting time and money on supplements that don’t work, our 17 Supplement Guides will help you figure out precisely what to take — and what to skip — based on your health goals and the latest scientific evidence. There’s a reason why over 50,000 customers rely on Examine.com’s independent and unbiased analysis.

Includes free lifetime updates so you always have the most accurate information.


I want unbiased recommendations to improve my health »

How to Take

Medical Disclaimer

Recommended dosage, active amounts, other details

Testosterone boosting effects in rats have been noted at a dosage of 200mg/kg of a 40% extract (80mg/kg Icariin), and based on body weight conversions from rats to humans[1] this results in an estimated human dose of:

  • 900mg Icariin for a 150lb person

  • 1,200mg Icariin for a 200lb person

  • 1,500mg Icariin for a 250lb person

Studies that use a lower dosage of Icariin (1-10mg/kg) are approximately equal to:

  • 11-110mg Icariin for a 150lb person

  • 15-150mg Icariin for a 200lb person

  • 18-180mg Icariin for a 250lb person

The human study on postmenopausal women and bone health noted that 60mg Icariin daily was active, and might serve as the lowest active dose currently known. It also appears to fall within the above range of lower active dosages which show benefits in rats.

Get the latest information on 400+ supplements and their effects on 600+ health conditions & outcomes.

By becoming an Examine Plus member, you'll have access to all of the latest nutrition research. Quickly and easily look up scientific research on over 400 supplements across over 600 different health goals, outcomes, conditions, and more.

Already a subscriber to any of our membership plans? Click here to login.

Human Effect Matrix

Unlocked for Examine Plus members

The Human Effect Matrix summarizes human studies to tell you what effects Horny Goat Weed has on your body, how much evidence there is, and how strong these effects are.

Full details are available to Examine Plus members.
Grade Level of Evidence
Robust research conducted with repeated double-blind clinical trials
Multiple studies where at least two are double-blind and placebo controlled
Single double-blind study or multiple cohort studies
Uncontrolled or observational studies only
Level of Evidence
? The amount of high quality evidence. The more evidence, the more we can trust the results.
Outcome Magnitude of effect
? The direction and size of the supplement's impact on each outcome. Some supplements can have an increasing effect, others have a decreasing effect, and others have no effect.
Consistency of research results
? Scientific research does not always agree. HIGH or VERY HIGH means that most of the scientific research agrees.
Notes
grade-c Minor - See study
The rate of bone loss over 2 years has been noted to be reduced with icariin supplementation, although not to a remarkable degree
grade-c - Very High See 2 studies
No significant influence on serum estrogen levels

Studies Excluded from Consideration

  • Excluded due to language barrier[2]

Become an Examine Plus member to access the latest nutrition research on over 400 supplements across over 600 different health goals, outcomes, conditions, and more.

Becoming an Examine Plus member not only unlocks the Human Effect Matrix for supplements, but also all health topics on Examine.com. We neatly summarize all the latest research so you can make the best decisions for your health based on what's accurate and not out-dated information.

Things to Note

Primary Function:

Also Known As

Epidemium, Herba Epimdii, Icariin, Yinyanghuo, Fairy Wings, Rowdy Lamb Herb

Do Not Confuse With

Icariin (active ingredient)

Goes Well With

  • Icariin is non-stimulatory.

  • Icariin has pro-erectile properties in males and is seen as a libido enhancer in both genders

Tired of misinformation? Get unbiased info on supplements.

At Examine.com, our incentives line up with yours — getting unbiased information. It’s why we don’t sell any advertising or supplements.

Join over 250,000 people who’ve learned about effective versus overrated supplements, supplement buying tips, and how to combine supplements for safety and efficacy.

Click here to see all 46 references.