Description
Epimedium , also known as barrenwort , bishop's hat , fairy wings , horny goat weed , or yin yang huo (Chinese: 淫羊藿; pinyin: Yínyánghùo ; Wade–Giles: Yin²-yang²-huo⁴ ), is a genus of flowering plants in the family Berberidaceae. The majority of the species are endemic to China, with smaller numbers elsewhere in Asia, and a few in the Mediterranean region.
Epimedium species are deciduous or evergreen hardy perennials. The majority have four-parted "spider-like" flowers in spring.
The species used as a dietary supplement is Epimedium grandiflorum. It contains icariin, which is a weak PDE5 inhibitor, in vitro. Its clinical effects are unknown. While there is little clinical evidence to date, as sildenafil, vardenafil, and tadalafil - sold under the brand names Viagra, Levitra and Cialis - are all based on (stronger) PDE5 inhibitory action, it is thought to have erectogenic properties and is found in some men's sexual health supplements.
