Sildenafil is also used in both men and women to treat the symptoms of pulmonary arterial hypertension. John’s wort. This can happen if you are sick with fever, diarrhea, or vomiting; sweat a lot; or do not drink enough liquids. Sildenafil usually should not be taken more than once every 24 hours. Sildenafil may cause side effects. When oral medications might not be safe Check with your health care team before you take any medicine for erectile dysfunction. Before taking sildenafil, tell your doctor and pharmacist if you are allergic to sildenafil, any other medications, or any of the ingredients in sildenafil tablet or suspension.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 adults (Liqrev, Revatio) and children 1 year of age and older (Revatio) with pulmonary arterial hypertension (PAH; high blood pressure in the vessels carrying blood to the . AdSave Time & Money with Online Prescription for Viagra, Cialis, Sildenafil and Tadafil. Free & Private Online Consultant with Real Doctors. Reliable E.D. Meds Shipped DiscreetlyK+ visitors in the past monthTypes: Sexual Health · Privacy Policy · Premature Ejaculation. Drug Images. What is Viagra? If you have erectile dysfunction (ED), your doctor may recommend that you take Viagra. It’s a prescription drug that’s used in adult males* with ED. With ED, you.