Tadalafil is used to treat men who have erectile dysfunction (also called sexual impotence). Tadalafil belongs to a group of medicines called phosphodiesterase 5 (PDE5) inhibitors. These medicines prevent an enzyme called phosphodiesterase type-5 from working too quickly. The penis is one of the areas where this enzyme works.
Erectile dysfunction is a condition where the penis does not harden and expand when a man is sexually excited, or when he cannot keep an erection. When a man is sexually stimulated, his body's normal response is to increase blood flow to his penis to produce an erection. By controlling the enzyme, tadalafil helps to maintain an erection after the penis is stroked by increasing blood flow to the penis. Without physical action to the penis, such as that occurring during sexual intercourse, tadalafil will not work to cause an erection.
Tadalafil is also used to treat men who have signs and symptoms of benign prostatic hyperplasia (BPH). BPH is caused by an enlarged prostate. Men with BPH usually have difficulty urinating, a decreased flow of urination, hesitation at the beginning of urination, and a need to get up at night to urinate. Tadalafil will make these symptoms less severe and reduce the chance that prostate surgery will be needed. This medicine is also used to treat erectile dysfunction and signs and symptoms of BPH.
Tadalafil is also used in both men and women to treat the symptoms of pulmonary arterial hypertension to improve your ability to exercise. This is high blood pressure that occurs in the main artery that carries blood from the right side of the heart (the ventricle) to the lungs. When the smaller blood vessels in the lungs become more resistant to blood flow, the right ventricle must work harder to pump enough blood through the lungs. Tadalafil works on the PDE5 enzyme in the lungs to relax the blood vessels. This will increase the supply of blood to the lungs and reduce the workload of the heart.