Viagra functions by blocking PDE-five from working. Using this method, blood flow on the penis can occur and never be stopped by PDE-5. This also widens your blood vessels to permit extra blood to flow into your penis.The AUC of the Lively metabolite, N-desmethyl sildenafil, was enhanced 62% by loop and potassium-sparing diuretics and 102% by nonsp… Read More