Indapamide. A review of its pharmacodynamic properties and therapeutic efficacy in hypertension.

Indapamide is an orally active sulphonamide diuretic agent. Although some evidence appears to indicate that the antihypertensive action of indapamide is primarily a result of its diuretic activity, only a limited diuresis occurs with the usual antihypertensive doses of 2.5 mg daily, and in vitro and in vivo data suggest that it may also reduce blood pressure by decreasing vascular reactivity and peripheral vascular resistance. In mild to moderate hypertension it is as effective as thiazide diuretics and beta-adrenergic blocking agents in lowering blood pressure when used as the sole treatment. Indapamide has been successfully combined with beta-adrenergic blocking agents, methyldopa, and other anti-hypertensive agents. While such findings need confirmation, it appears that indapamide shares the potential with other diuretic agents to induce electrolyte and other metabolic abnormalities, although it may do so with less frequency or severity. Thus, indapamide appears to offer a suitable alternative to more established drugs as a 'first-line' treatment in patients with mild to moderate hypertension. Whether it differs significantly from other diuretics when used as antihypertensive therapy, either in its mode of action or its side effect profile, needs further clarification.