Sildenafil belongs to a group of medicines called phosphodiesterase 5 PDE5 inhibitors. Sildenafil does not prevent pregnancy or the spread of sexually transmitted diseases such as human immunodeficiency virus HIV. This is a type of high blood pressure that occurs between the heart and the lungs. Take sildenafil as needed before sexual activity. When oral medications might not be safe Check with your health care team before you take any medicine for erectile dysfunction.Description and Brand Names. Drug information provided by: Merative, Micromedex® US Brand Name. Revatio; Viagra; Descriptions. Sildenafil is used to treat men who have . 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 . Sildenafil oral tablet is available as a brand-name drug and as a generic drug. Brand names: Viagra, Revatio. Sildenafil comes in three forms: an oral tablet, an oral .