SILDENAFIL - VIAGRA COMMON USES: Sildenafil ( sil-DEN-a-fil) belongs to a group of medicines that delay the enzymes called phosphodiesterases from working too quickly. The penis is one of the areas where these enzymes work. Sildenafil is used to treat men who have erectile dysfunction (also called sexual impotence). By controlling the enzyme phosphodiesterase, sildenafil helps to maintain an erection that is produced when the penis is stroked. Without physical action to the penis, such as that occurring during sexual intercourse, sildenafil will not work to cause an erection. Sildenafil is also used to treat the symptoms of pulmonary arterial hypertension. This is the 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. Sildenafil helps by increasing the supply of blood to the lungs and reducing the workload of the heart. STORAGE CONDITIONS: To store this medicine: Keep out of the reach of children. Store away from heat and direct light. Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down. Keep the medicine from freezing. Do not refrigerate. Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.