Aphrodisiac Research Horny Goat Weed's aphrodisiac effects have been verified in both animal and human research. Mice treated with a Horny Goat Weed preparation produced "apparent effects on the improvement of sexuality." It has also shown to improve sperm producing capability. Since Horny Goat Weed has been traditionally used for kidney disease, it's interesting that research ahs demonstrated a sexual potentiation effect and improved quality of life in patients with chronic renal failure who were given Horny Goat Weed. Mechanisms of Action Research has shown that Horny Goat Weed significantly increases testosterone in mice. This certainly appears to be the herb's mechanism of action, although Horny Goat Weed may have more than one. For example, it has been established that sexual arousal is linked to activity of cholinergic neurotransmitters. However, an enzyme called acetyl-cholinesterase (AchE) inactivates cholinergic neurotransmitters within 1/500 of a second. As it turns out