Effects of verapamil in hypertensive patients

In fifteen patients with uncomplicated essential hypertension verapamil reduced systolic as well as diastolic blood pressure by virtue of a decrease in total peripheral vascular resistance. Renal vascular resistance also fell, but renal perfusion was well maintained. Although levels of renin and angiotensin II remained unchanged, aldosterone levels fell significantly. Noradrenaline levels rose slightly, but changes were not significant. On the other hand adrenaline was significantly reduced. Renal sodium excretion was markedly enhanced, perhaps secondary to aldosterone suppression. Despite sodium loss, plasma volume increased suggesting that verapamil not only lowers arterial but also venous resistance.