Udenafil

The drug udenafil, marketed under the trade name Zydena, is within the PDE₅ inhibitor class (which also includes avanafil, sildenafil, tadalafil, and vardenafil). Used, like other PDE₅ inhibitors, to treat erectile dysfunction, udenafil was developed by Dong-A Pharmaceutical. With action of fairly rapid onset (peak plasma concentration after 1 to 1.5 hours) yet long duration (plasma half life of 11 to 13 hours), udenafil's pharmacokinetics allows once-daily dosage (in addition to on-demand use). Typical doses are 100 and 200 mg. Udenafil is available in Korea, Russia, and the Philippines; in the United States, it has not been approved by the U.S. Food and Drug Administration.