IRBESARTAN - A REVIEW OF ITS PHARMACODYNAMIC AND PHARMACOKINETIC PROPERTIES AND THERAPEUTIC USE IN THE MANAGEMENT OF HYPERTENSION

Irbesartan inhibits the activity of angiotensin II (AII) via specific, selective non-competitive antagonism of the AII receptor subtype 1 (A T(1)) which mediates most of the known physiological activities of AII . In patients with mild to moderate hypertension, once daily administr ation of irbesartan 150 or 300mg, with or without adjunctive antihyper tensive agents, provides effective 24-hour BP control. Irbesartan redu ced BP to a similar extent to enalapril and atenolol and to a signific antly greater extent than losartan. The combination of irbesartan and hydrochlorothiazide resulted in additive antihypertensive effects. The drug is effective in the elderly and dosage adjustment is not require d in these patients or in those with renal or hepatic failure. Prelimi nary studies evaluating the efficacy of irbesartan in patients with he art failure have produced encouraging results. Irbesartan is very well tolerated and neither the frequency nor the pattern of adverse events differed from those seen in placebo recipients, although headache was significantly more frequent with the latter. Similarly, the incidence of adverse events did not differ significantly between irbesartan and enalapril in patients who received either drug as monotherapy. Headac he, upper-respiratory tract infection and musculoskeletal pain were th e most common complaints.Thus, irbesartan is an effective therapy for patients with mild to moderate hypertension and had an adverse event p rofile similar to that of placebo in clinical trials. On this basis it would appear to be an effective therapeutic option in this indication .