Sildenafil is the active ingredient of Fildena. Fildena is the most effective erectile dysfunction therapy. Fildena comes in a variety of strengths. Fildena 100 is taken one hour before sexual activity and has a five- to six-hour duration. Fildena should be used just once per day. Fildena is the most widely used and successful male enhancement drug available. Visit medzsite.com for more details.