Fildena 100 is a brand name for sildenafil citrate, which is the same active ingredient found in Viagra. Sildenafil is commonly used to treat erectile dysfunction (ED). In many countries, including the United States, sildenafil is available only with a prescription from a healthcare provider. It's important to consult with a healthcare professional before taking any medication like Fildena 200 , to ensure it is safe and appropriate for your individual health needs.