Megalis 10 mg, a generic version of Tadalafil is a popular drug which relaxes muscles and increases blood flow to specific areas of the body. It is primarily used to treat erectile dysfunction in men as well as symptoms of benign prostatic hypertrophy. Tadalafil is also used to improve the ability to exercise in people with pulmonary arterial hypertension (PAH). Tadalafil treats PAH by relaxing the blood vessels in the lungs to allow blood to flow more easily. Tadalafil is a result-oriented drug that is sold under various brand names and in varied dosage forms like tablets and oral jellies. Megalis has Tadalafil as the main active ingredient. Tadalafil is a phosphodiesterase-5 enzyme inhibitor. It can control the activity of this enzyme. Tadalafil stops the activity of this enzyme and improves the blood flow to the penis which makes it firm and erect. Erection can be easily achieved by using Tadalafil.