Box , Mission, KS If your pharmacy does not participate, you may be able to submit a request for a rebate in connection with this Savings Offer. These are commonly prescribed for an enlarged prostate or male pattern baldness. Vardenafil usually works for 4 to 5 hours. They include dutasteride Avodart, Jalyn and finasteride Propecia, Proscar. How oral medicines differ Each oral medicine for ED has a slightly different chemical makeup. Sildenafil Viagra.What is Viagra? Viagra relaxes muscles found in the walls of blood vessels and increases blood flow to particular areas of the body. Viagra is used to treat erectile . 1. How it works. Sildenafil may be used to treat erectile dysfunction (ED or impotence) in men (Viagra brand) or pulmonary arterial hypertension in both men and . What is Viagra? If you have erectile dysfunction (ED), your doctor may recommend that you take Viagra. It’s a prescription drug that’s used in adult males* .