Fildena is a well-known generic medication used to treat erectile dysfunction (ED) in men. It contains Sildenafil Citrate, the same active ingredient as Viagra, and is manufactured by Fortune Healthcare. Fildena works by enhancing blood flow to the penis during sexual arousal, helping men achieve and maintain an erection. Fildena is a PDE5 inhibitor, which relaxes the blood vessels in the penis, allowing more blood to flow during sexual stimulation.