Regular use of sildenafil lowers BP in patients with hypertension, according to researchers in the United Kingdom. Still, its use in clinical practice may be limited by its relatively short duration of action, they concluded. Longer-acting phosphodiesterase-(PDE)-5 inhibitors, however, may be quite useful as antihypertensive agents.
In a randomized, double-blind, two-way crossover study by David J. Webb, MD, and his colleagues at the University of Edinburgh, 25 otherwise-untreated patients with hypertension received 50 mg of sildenafil or placebo three times daily for 16 days. Study end points included changes in ambulatory and clinic BP, arterial wave reflection, carotid-femoral pulse wave velocity, and brachial artery flow-mediated dilation.
Sildenafil significantly reduced both systolic and diastolic ambulatory 24-hour, daytime, and nighttime BP compared with both baseline and placebo, Dr. Webb’s research group reported in Hypertension (2006; 48:622-627). The reduction in average daytime BP in patients receiving sildenafil was 8/6 mm Hg compared with baseline and about 10/6 mm Hg compared with placebo.
Sildenafil significantly reduced clinical BP compared with placebo (change from baseline to 1 hour after drug administration) on study day 16: Systolic BP declined by 5 mm Hg with sildenafil but rose 4 mm Hg with placebo; diastolic BP decreased by 5 mm Hg with sildenafil and increased by 2 mm Hg with placebo.