Detailed Sildenafil dosage information for adults, the elderly and children. Includes dosages for Erectile Dysfunction and Pulmonary Hypertension; plus renal, liver and dialysis adjustments., Below are the general guidelines for dosing sildenafil. Note that these dosages may be adjusted on a case-by-case basis for individual patients by a provider., Sildenafil is used to treat men who have erectile dysfunction (also called sexual impotence). Sildenafil belongs to a group of medicines called phosphodiesterase 5 (PDE5) inhibitors., Sildenafil is a phosphodiesterase inhibitor used for the treatment of erectile dysfunction. In eliciting its mechanism of action, sildenafil ultimately prevents or minimizes the breakdown of cyclic guanosine monophosphate (cGMP) by inhibiting cGMP specific phosphodiesterase type 5 (PDE5) 11, 12, 13, 14, 15, 16, 8, 9., Viagra is a brand name for the drug sildenafil. It is primarily prescribed for treating ED. ED is when a man struggles to achieve or maintain an erection during sexual activity, often called, Sildenafil tablets, USP, an oral therapy for erectile dysfunction, is the citrate salt of sildenafil, a selective inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type .