Before starting, stopping, or changing any medications while taking sildenafil, please get the advice of your doctor or pharmacist. You are encouraged to report adverse events related to Viatris products by calling U. An OTC drug will help patients get treatment more quickly. If you are taking sildenafil for PAH, take the missed dose as soon as you remember it. Rarely reported side effects include: an erection that will not go away priapism. 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. If you have certain health conditions or are taking certain medications, your doctor may tell you to take sildenafil less often.Generic Viagra (sildenafil) is an alternative to the branded Viagra drug that can be used for treating erectile dysfunction (ED). It’s now sold by many manufacturers, including online. The Savings Offer and Program expire on 12/31/ For further information, call , visit , or write: Viatris Inc., P.O. Box , Mission, KS . According to price-comparison site , generic Revatio will cost you as little as $ per pill, depending on where you fill your prescription. That’s compared with .