These include itraconazole Sporanox, Tolsura , ketoconazole Extina, Ketozole, others and ritonavir Norvir. It might work longer if you have mild to moderate erectile dysfunction. Oral medicines for ED usually work well and cause few side effects. They’re often the first line of treatment for trouble getting or keeping an erection, called erectile dysfunction ED. It lasts 4 to 5 hours, or longer if you have mild to moderate ED. Recent heart or blood vessel problems.Breastfeeding For professionals Drug Images What is Viagra? Viagra is a brand-name prescription drug that’s approved to treat erectile dysfunction (ED). With ED, you’re . It will get the doctor’s attention, and it will help make sure the man will actually bring up the subject. See a sex therapist. The name “sex therapist” may sound intimidating. VIAGRA can cause serious side effects. Rarely reported side effects include: an erection that will not go away (priapism). If you have an erection that lasts more than 4 hours, get .