Stop taking VIAGRA and call your healthcare provider right away if you have any sudden vision loss sudden hearing decrease or hearing loss. Concomitant administration of strong CYP3A4 inducers, such as rifampin, is expected to cause greater decreases in plasma levels of sildenafil. This finding is consistent with the inhibition of PDE6, which is involved in phototransduction in the retina. If you prefer, you may contact the U. Two of the questions from the IIEF served as primary study endpoints; categorical responses were elicited to questions about 1 the ability to achieve erections sufficient for sexual intercourse and 2 the maintenance of erections after penetration. The titration studies, in which most patients received mg, showed similar results. Patients should always ask their doctors for medical advice about adverse events.(sildenafil citrate) is prescription medicine used to treat erectile dysfunction (ED). VIAGRA is not for women or children. Prescribing Info. Patient Prescribing Information. Terms and . AdGet a Prescription for ED treatment, discreetly deliverED to your ive Offers · How It Works · Get More InfoService Catalog: P.E. Treatments, GET MORE INFO, Terms & Conditions and more. AdWe Have Health & Personal Care Items From Hundreds Of Popular Brands In Stock For You. Get Deals and Low Prices On endurance pills for men On Amazon.