Fildena 25 mg contains sildenafil, a PDE5 inhibitor used to treat erectile dysfunction (ED). Sildenafil improves blood flow to the penis during sexual stimulation, helping men achieve and maintain an erection. A 25 mg dose is an available sildenafil strength and may be selected when a lower dose is appropriate based on effectiveness, tolerability, or certain medical factors. It should be used according to a healthcare professional's advice.