Fildena 100 is a prescription medication used to treat erectile dysfunction (ED) in men. The active ingredient in Fildena 100 is sildenafil citrate, which is also the main component in the brand-name drug Viagra. Fildena 100 works by increasing blood flow to the penis during sexual stimulation, allowing for a firm and sustained erection. It is often chosen by men seeking a more affordable alternative to Viagra with the same active ingredient and comparable effectiveness.