The patent on Revatio indicated for pulmonary arterial hypertension rather than erectile dysfunction expired in late How oral medicines differ Each oral medicine for ED has a slightly different chemical makeup. They’re often the first line of treatment for trouble getting or keeping an erection, called erectile dysfunction ED. The information provided is for educational purposes only and is not intended to replace discussions with a healthcare provider. 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.The four main medicines taken by mouth for erectile dysfunction are: Avanafil (Stendra). Sildenafil (Viagra). Tadalafil (Cialis). Vardenafil. These medicines are called . Cost Overdose Ask your doctor Q&A Drug Images What is Viagra? If you have erectile dysfunction (ED), your doctor may recommend that you take Viagra. It’s a . CHOOSE BRAND-NAME VIAGRA. The original little blue pill prescribed by doctors for over 20 years. Clinically proven to treat men with erectile dysfunction (ED) Ongoing .