Brand names Why is this medication prescribed? Be sure to let your doctor and pharmacist know that you are taking these medications before you start taking sildenafil. You may opt-out of email communications at any time by clicking on the unsubscribe link in the e-mail. If you are taking sildenafil to treat erectile dysfunction, you should know that it does not cure erectile dysfunction or increase sexual desire. John’s wort. Sildenafil is also used in both men and women to treat the symptoms of pulmonary arterial hypertension.Sildenafil (Viagra). Tadalafil (Cialis). Vardenafil. These medicines are called PDE5 inhibitors. They enhance the effects of a chemical the body makes that relaxes . 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 . 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 .