Levitra (Vardenafil) belongs to a group of medicines that delay the enzymes (proteins in your body) called phosphodiesterases from working too quickly. The penis is one of the areas where these enzymes work. Levitra is used to treat men who have erectile dysfunction (also called sexual impotence). 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. Levitra may help a man get and keep an erection when he is sexually excited. Levitra helps to increase the blood flow to the penis and may help men with erectile dysfunction get and keep an erection satisfactory for sexual activity. Once a man has completed sexual activity, blood flow to his penis decreases, and his erection goes away. Levitra does not help to cure erectile dysfunction.