Horny Goat Weed and Testosterone: Potent Testosterone Mimetic
By Ali Kuoppala | Last reviewed Tue 25 September 2018
Medical Review by Gerardo Sison, PharmD
Horny Goat Weed (Epimedium) is a flowering herb that grows in the Mediterranean region of Asia.
It’s used as an aphrodisiac in the Chinese medicine dates back thousands of years, and most recently even the western medicine has noted the existence of this potent libido booster, and one study shows that it has great potential to increase testosterone.
This is what I’m talking about:
Horny Goat Weed as a pro-erectile Testosterone Booster
Horny Goat Weed has an active ingredient that’s known for its inhibitory effect on the PDE-5 enzyme.
The compound is called icariin, and even though it’s not as strong of a PDE-5 blocker as Viagra or Cialis (ED drugs work by inhibiting the PDE-5 enzyme synthetically), it still has some beneficial effects on erectile health and libido.
Few studies have also found out that icariin mimics and increases testosterone levels.
Here’s a quick look at the science of this herb:
a) This rat study found out that an 80 mg’s/kg dose of icariin was able to triple testosterone levels in rats without changing luteinizing hormone (LH) or follicle stimulating hormone (FSH) levels. The researchers claim that icariin doesn’t stimulate the hypothalamus-pituitary-testicles axis like most of the herbal testosterone boosters to do, but it works as a testosterone mimetic inside the testicles and thus doesn’t change the levels of LH and FSH.
b) This in-vitro study found out that icariin is one of the few known natural PDE-5 inhibitors, and thus could be used as a natural erectile dysfunction relief. The same study was also used as evidence in the patent infringement case to rescind parts of the U.S. Viagra patent (in the patent the Viagra manufacturers claimed that their chemically synthesized drug was the only compound on the earth that inhibited PDE-5).
c) Few studies have also found out that the active ingredient of Horny Goat Weed – icariin – stimulates nitric oxide production, increases NO levels, and improves blood flow in-vitro and in-vivo (study, study). The increase in nitric oxide in combination with the inhibition of PDE-5 means that Horny Goat Weed definitely has some pro-erectile benefits.
d) According to this study, icariin increases nerve growth and blood flow in the pelvic region.
e) Some animal studies have found out that icariin blunts high cortisol levels (study, study).
Based on the findings above, icariin (the active ingredient of Epimedium) should improve erection quality and blood flow through 3 step process. Firstly by inhibiting the PDE-5 enzyme, secondly via increasing nitric oxide levels, and thirdly by increasing blood flow in the pelvic region.
Icariin also mimics testosterone inside the gonads and seemingly relieves stress by lowering cortisol levels, but the effects have not been studied in humans (yet).
Conclusion
Horny Goat Weed is most definitely an aphrodisiac with pro-erectile qualities.
Most of the benefits are due to the high icariin content, which has also shown some testosterone mimetic properties. Horny Goat Weed also contains at least 37 different flavonoids and is an extremely strong antioxidant, which should furthermore improve its pro-erectile testosterone boosting qualities…
…But until there are human studies to prove its effects, we can’t be sure, albeit the studies so far seem extremely promising.
If you’re going to supplement with icariin, my recommendation is to go with Barlowe’s Extract.