If you become pregnant while taking sildenafil, call your doctor. Some medications should not be taken with sildenafil. Tell your doctor if any of these symptoms are severe or do not go away: headache. The symptoms, diagnosis, and the treatments. This device uses a hollow tube to create a vacuum that pulls blood into your penis. However, if you take sildenafil with a high-fat meal, it will take longer for the medication to start to work. Patients should always ask their doctors for medical advice about adverse events.In many cases, erectile dysfunction is caused by something physical. Common causes include: Heart disease. Clogged blood vessels (atherosclerosis) High cholesterol. High . What is sildenafil? Sildenafil is a prescription drug. It comes in the form of a tablet and suspension (liquid). Both are taken by mouth. It also comes in an intravenous (IV) form, which is only. Clinically proven to treat men with erectile dysfunction (ED) Ongoing commitment to product quality and safety monitoring Learn More IF YOU CHOOSE BRAND-NAME VIAGRA, .