Selective Alpha-1 Inhibitors: First-or Second-Line Antihypertensive Agents?

Abstract

It is well documented that in the treatment of mild or moderate hypertension selective α₁-inhibitors such as doxazosin and prazosin lower blood pressure to approximately the same extent as β-blockers, diuretics, ACE inhibitors and calcium antagonists. However, treatment with selective αi-inhibitors is also associated with a number of other favourable effects. For example, in contrast to most β-blockers, selective αi-inhibitors have a favourable effect on serum lipids, primarily lowering the triglycerides but also increasing the ratio of high-density lipoprotein (HDL) cholesterohtotal cholesterol. In addition, selective αi-inhibitors do not aggravate glucose metabolism or increase uric acid concentration, as thiazide diuretics frequently do. Some patients gain particular benefit from treatment with a selective α₁-inhibitor, namely those with non-insulin-dependent diabetes mellitus, peripheral vascular disease, chronic obstructive pulmonary disease, and kidney failure. While no controlled mortality trials with selective α₁-inhibitors have yet been completed, new vasodilator drugs such as these do lower blood pressure in a more physiological manner than traditional antihypertensive agents, and appear to cause fewer side effects. In this respect, with the exception of patients with manifest or strongly suspected coronary heart disease who are not receiving β-blocker treatment, selective α₁-inhibitors should be recommended as first-line agents for the treatment of hypertension.