Fildena is a brand of medication used to treat erectile dysfunction (ED) in men. It contains Sildenafil Citrate as its active ingredient, which is a phosphodiesterase type 5 (PDE5) inhibitor. Fildena works by increasing blood flow to the penis during sexual stimulation, helping men achieve and maintain an erection. The effects of Fildena can last for approximately 4 to 6 hours, but the specific duration varies among individuals.