Erectile Dysfunction and Sexual Dysfunction in Women
According to folklore, horny goat weed’s reputed aphrodisiac qualities were discovered when a Chinese goat herder noticed increased sexual activity in his flock after they ingested the weed.

Animal studies indicate that horny goat weed may work by increasing nitric oxide levels, which relaxes smooth muscle and lets more blood flow to the penis or clitoris.

Horny goat weed also appears to act by inhibiting the PDE-5 enzyme, which is the same way that the popular drug Viagra works.

Some evidence suggests horny goat weed may modulate levels of the hormones cortisol, testosterone, and thyroid hormone, bringing low levels back to normal.