Tell your doctor or pharmacist if you are taking nitrates medications for chest pain such as isosorbide dinitrate Isordil , isosorbide mononitrate Monoket , and nitroglycerin Nitromist, Nitro-Dur, Nitrostat. Also tell your doctor if you or any of your family members have or have ever had an eye disease such as retinitis pigmentosa an inherited eye condition that causes loss of vision or if you have ever had sudden severe vision loss, especially if you were told that the vision loss was caused by a blockage of blood flow to the nerves that help you see. Sorry something went wrong with your subscription Please, try again in a couple of minutes Retry. And what about drugs that decrease the effect of Viagra on your erections? You may opt-out of email communications at any time by clicking on the unsubscribe link in the e-mail.Learn about uses, how it works, and more for Viagra (sildenafil). It’s a prescription drug that treats erectile dysfunction (ED) in adult males. Sildenafil (Liqrev, Revatio) is used to improve the ability to exercise in adults (Liqrev, Revatio) and children 1 year of age and older (Revatio) with pulmonary arterial . Oral medicines for ED usually work well and cause few side effects. The four main medicines taken by mouth for erectile dysfunction are: Avanafil (Stendra). .