Malegra Professional contains sildenafil citrate, which is a phosphodiesterase type 5 (PDE5) inhibitor. It works by increasing blood flow to the penis during sexual stimulation, helping men achieve and maintain an erection suitable for sexual activity. Before taking Malegra Professional, inform your doctor about any medical conditions you have, especially if you have heart problems, high or low blood pressure, liver or kidney disease, bleeding disorders, or a history of priapism (prolonged erection).