Phosphodiesterase-5 inhibitors and their hemodynamic effects

Erectile dysfunction occurs commonly in untreated and treated hypertensive patients, impairing adherence to treatment and quality of life. Furthermore, it is a marker for enhanced risk for cardiovascular disease. Phosphodiesterase type 5 (PDE5) inhibitors, sildenafil, vardenafil, and tadalafil, provide effective treatment of erectile dysfunction. They reduce blood pressure in healthy patients: sildenafil 100 mg, -3.7/-3.6 mm Hg; vardenafil 20 mg, -7.5/-8 mm Hg; and tadalafil 20 mg, -1.6/-0.8 mm Hg. Greater declines in blood pressure with a PDE5 inhibitor may be observed in treated and untreated hypertensive patients. The additive effect of PDE5 inhibitors with one or multiple antihypertensive drugs is modest. alpha(1)-Blockers, except tamsulosin, may result in larger declines in blood pressure and cause orthostatic hypotension. Thus, caution should be exercised by using the lowest doses of proportional, variant(1)-blockers and PDE5 inhibitors in combination. Nitrates in combination with PDE5 inhibitors cause a profound decline in blood pressure and are contraindicated.