generic cialis here buy cialis online buy cialis 40mg here buy cialis without prescription online associate professor of urology at Adverse events looking for cheap viagra online? 150mg viagra for sale The cardiac effects associated with sildenafil have been studied extensively. Sildenafil is absolutely contraindicated in patients taking nitrates such as nitroglycerin or isosorbide. This is because sildenafil, like the other PDE-5 inhibitor medications, can potentiate the vasodilatory effects of the nitrate-based medication, resulting in an exaggerated vasodilatory effect that is potentially dangerous. Patients with serious cardiac disease, with exertional angina, or taking multiple antihypertensive medications are advised to seek the advice of a cardiologist before beginning therapy with sildenafil. A number of studies examining the cardiac effects of sildenafil have conclusively shown that no adverse consequences exist under normal circumstances.