A Transdermal Formulation of Icariin for Use as a Substitute for Sildenafil and a Showing of No Clinical Efficacy

Icariin, considered to be the active compound in the herb Epimedium (also known as Horny Goat Weed) has been shown to be possibly erectogenic in a variety of animal studies, leading to its popularity as an herbal supplement for ED even though there are essentially no human studies supporting its effectiveness. Icariin is highly insoluble, and many studies have additionally reported that Icariin is not absorbed in the gut due to a very low bioavailability. The purpose of this study was to solubilize Icariin in the formulation of a transdermal cream which would deliver the compound directly to the blood stream bypassing poor intestinal absorption; and by informal testing of the transdermal cream on volunteer subjects, to determine if the erectogenic effects of icariin could be improved. This study demonstrates that icariin, delivered via the transdermal route, failed to demonstrate any efficacy of icariin for ED, conforming to another recent study reporting no effect upon oral adminstration.