Malegra 100 mg is a medication used to treat erectile dysfunction (ED) in men. It contains Sildenafil Citrate, the same active ingredient found in Viagra. Sildenafil belongs to the class of drugs called PDE5 inhibitors, which work by relaxing the blood vessels in the penis, allowing for increased blood flow during sexual stimulation. Malegra 100 mg is typically taken 30 to 60 minutes before sexual activity, and its effects can last for 4 to 6 hours. It helps men achieve and maintain an erection, but only when they are sexually aroused.