Fildena 100 is a medication containing sildenafil citrate, primarily used to treat erectile dysfunction (ED) in men. As a phosphodiesterase type 5 (PDE5) inhibitor, Fildena 100 works by increasing blood flow to the penis during s*xual stimulation, which helps achieve and maintain an erection. It is similar to Viagra, sharing the same active ingredient and function. Typically, Fildena 100 is taken about 30 minutes to an hour before s*xual activity, and its effects can last up to 4-6 hours.