Continue to take sildenafil even if you feel well. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Your doctor may adjust your dose if needed. Remove the syringe from the bottle. Ask your pharmacist for a list of the ingredients. Sorry something went wrong with your subscription Please, try again in a couple of minutes Retry. Dosing The dose of this medicine will be different for different patients.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 .  · Proper Use. Drug information provided by: Merative, Micromedex ®. Use sildenafil exactly as directed by your doctor. Do not use more of it and do not use it more . Cost. Overdose. Ask your doctor. Q&A. Drug Images. What is Viagra? If you have erectile dysfunction (ED), your doctor may recommend that you take Viagra. It’s a .