Epimedium, also known as Yin Yang Huo or Horny Goat Weed, had been a powerful remedy in Traditional Chinese Medicine for thousands of years. Epimedium is an ivy-like ground shrub of the higher and drier areas of China and Tibet. The name of the epimedium in Mandarin, yin yang huo, translates as "weed for licentious goat." Legend has it that a goat herder discovered the properties of epimedium by observing his billy goats uncontrollable sexual appetites after they grazed on the herb. TCM practitioners use this herb used to increase the Yang energies, for instance, it would be used to enhance male sexual performance. Epimendium is a member of an elite group of herbs that slow down aging and promote longevity. True to it's name, horny goat weed promotes male potency by increasing blood flow to the penisas and acting as an aphrodisiac.

Unlike the many herbs that have estrogenlike effects, epimedium is an unusual herb in that it has testosteronelike effects. It stimulates sexual activity in both men and women, increases sperm production, stimulates the sensory nerves, and increases sexual desire. ⁽¹⁾