Some people may also have ringing in their ears tinnitus or dizziness. Oral medicines for ED usually work well and cause few side effects. However, if you take sildenafil with a high-fat meal, it will take longer for the medication to start to work. If your doctor is concerned your ED is an indicator of a more serious problem, they may send you to a specialist who can run some additional tests. 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 lungs, causing shortness of breath, dizziness, and tiredness. Your doctor or other health care professional can recommend one for you based on these factors, other health conditions you have and any other medicines you take.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 . Can I buy generic Viagra over the counter or do I need a prescription? In the U.S. and most. 1. How it works Sildenafil may be used to treat erectile dysfunction (ED or impotence) in men (Viagra brand) or pulmonary arterial hypertension in both men and women (Revatio .