The active ingredient in Kamagra is sildenafil citrate. Sildenafil works by inhibiting PDE5, which helps relax the blood vessels in the penis and promotes increased blood flow, leading to the ability to achieve and sustain an erection. Kamagra is a prescription medication. It's essential to consult with a healthcare provider before using it. They can assess your specific condition, provide dosage recommendations, and ensure it is safe and appropriate for you.