Malegra Pro 100 mg is a medication used to treat erectile dysfunction (ED) in men. It contains sildenafil citrate as its active ingredient. Sildenafil is a phosphodiesterase type 5 (PDE5) inhibitor that works by increasing blood flow to the penis, facilitating the ability to achieve and maintain an erection during sexual stimulation. Sildenafil typically has a duration of action of around 4 to 6 hours, providing a window of time during which sexual activity can occur.