Horny Goat Weed (Epimedium) is an ornamental plant that also has a long history of traditional use in Chinese herbalism. It was viewed as a potent tonic that was used for male sexual health and libido support in both men and women. Epimedium was thought to "tonify life's gate"---a term used to refer to the "vital energy" in men. NOW® Horny Goat Weed Extract is standardized to icariins and is combined with maca, another vitality herb.