http://en.wikipedia.org/wiki/Icariin http://en.wikipedia.org/wiki/Icariin ;
Effects of icariin on phosphodiesterase-5 activity in vitro and cyclic guanosine monophosphate level in cavernous smooth muscle cells. Ning H et al. Urology. 2006 Dec;68(6):1350-4.
The pharmacological and toxicological properties of this product have not been fully investigated. Exercise caution in use and handling. This product must not be used in humans.