Concomitant administration of strong CYP3A4 inducers, such as rifampin, is expected to cause greater decreases in plasma levels of sildenafil. Protein binding is independent of total drug concentrations. United States Sildenafil is available as a generic drug in the United States, labeled for pulmonary arterial hypertension. The pattern of responses was similar for the other principal question, the ability to achieve an erection sufficient for intercourse. Similar values for pharmacokinetic parameters were seen in normal volunteers and in the patient population, using a population pharmacokinetic approach. Brand names Why is this medication prescribed? New Zealand Sildenafil was reclassified in New Zealand in so it could be bought over the counter from a pharmacist.Brand names for sildenafil include Viagra, Revatio, and Liqrev. The cost for sildenafil oral tablet mg is around $10 for a supply of 2 tablets, depending on the pharmacy you .  · Lemonaid Sildenafil Skip to review Best for bulk ordering Viagra and generic Viagra: Optum Store Viagra Best subscription service for Viagra and generic Viagra: Rex MD Viagra. 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 suspension (liquid), and an.