Angiotensin II antagonism in clinical practice: experience with valsartan.

Angiotensin (Ang) II antagonists provide specific and selective blockade of Ang II at the AT1 receptor, regardless of the enzymatic pathway of production. Valsartan has an affinity for the AT1 receptor 30,000 times that of the AT2 receptor. Valsartan is not a prodrug and undergoes little metabolism. It has a half-life of approximately 9 h, but duration of antihypertensive action at the usual dose of 80 or 160 mg daily is 24 h. The trough to peak ratio is 0.66. Valsartan has antihypertensive efficacy at least equivalent to that of established antihypertensive drugs and has additive effects in combination. The efficacy of valsartan appears to be independent of age, sex, and race. Valsartan is effective in hypertensive patients with renal insufficiency and is associated with maintenance of renal function. It is well tolerated, with a side-effect profile indistinguishable from that of placebo, and does not cause cough. Ang II antagonists are a promising class of cardiovascular drugs with considerable potential in clinical practice.