As with sildenafil, a high-fat meal or alcohol keep the body from absorbing it as quickly. When oral medications might not be safe Check with your health care team before you take any medicine for erectile dysfunction. To provide you with the most relevant and helpful information, and understand which information is beneficial, we may combine your email and site usage information with other information we have about you. Sildenafil treats PAH by relaxing the blood vessels in the lungs to allow blood to flow easily. 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. It lasts 4 to 5 hours, or longer if you have mild to moderate ED. Slowly pull back the plunger until the required dose.The Savings Offer and Program expire on 12/31/ For further information, call , visit , or write: Viatris Inc., P.O. Box , Mission, KS . Sildenafil (Viagra) is used to treat erectile dysfunction (impotence; inability to get or keep an erection) in men. Sildenafil (Liqrev, Revatio) is used to improve the ability to exercise in . Sildenafil (Viagra). Tadalafil (Cialis). Vardenafil. These medicines are called PDE5 inhibitors. They enhance the effects of a chemical the body makes that relaxes .