3Sildenafil is used to treat male sexual function problems (impotence orerectile dysfunction-ED). In combination with sexual stimulation, sildenafil works by increasingbloodflow to thepenisto help a man get and keep an erection Sildenafil belongs to a class of drugs called phosphodiesterase type 5 (PDE5) inhibitors. A class of drugs is a group of medications that work in a similar way. These drugs are often used to treat similar conditions. Sildenafil works in different ways, depending on the condition it's being used to treat. For ED: Sildenafil works by increasing blood flow to the penis. This helps you get or maintain an erection. Sildenafil only works for ED if you're sexually aroused. For PAH: Sildenafil works by relaxing the muscles and opening up the blood vessels in your lungs. This decreases the blood pressure in your lungs. Sildenafil slows down the progression of your illness. It also makes you more able to exercise. Get your copy today by scrolling up and clicking Buy Now to get your copy today