Zudena 100 mg Tablet is a medication used to treat erectile dysfunction (ED). Its active ingredient is sildenafil, which is the same active ingredient found in Viagra. Sildenafil works by increasing blood flow to the penis during sexual stimulation, which helps achieve and maintain an erection. Zudena 100 mg Tablet is typically taken about 30 to 60 minutes before sexual activity. It should be swallowed whole with water, and it can be taken with or without food.