The non-peptide angiotensin II receptor antagonists represent a new class of drugs with demonstrated efficacy in the treatment of hypertension. Eprosartan is a potent, orally active AT(1) receptor antagonist which is chemically distinct from losartan and other non-peptide angiotensin II receptor antagonists. Eprosartan has a high affinity for the angiotensin II AT(1) receptor, but does not interact with the AT(2) receptor, adrenergic receptors or other receptors involved in cardiovascular regulation. In contrast to most other angiotensin II antagonists, eprosartan is a true competitive antagonist of the AT(1) receptor. Eprosartan is effective in antagonising the cardiovascular and renal effects of exogenous angiotensin II in both experimental animals and humans. Furthermore, it is an effective antihypertensive agent when administered to renin-dependent hypertension animal models, and in patients with mild to severe hypertension. The antihypertensive effect of eprosartan is maintained over a 24-h interval following a single dose with no reported dose-dependent adverse side-effects.