The beneficial effect of antihypertensive pharmacotherapy in decreasing morbidity and mortality in hypertensive patients may be counteracted by metabolic and biochemical disturbances, such as hypokalemia, hyperglycemia, hyperuricemia, and hyperlipoproteinemia, that occur with the administration of thiazides and related diuretics. Antiatherogenic high-density lipoprotein cholesterol may be unchanged, whereas the potentially atherogenic low-density lipoprotein cholesterol may be increased by long-term therapy with thiazide diuretics. Indapamide is a methylindoline antihypertensive diuretic with a considerable peripheral vasodilatory effect. At a low dose of 2.5 mg daily, it did not alter total circulating cholesterol, in contrast to chlorthalidone. High-density lipoprotein cholesterol levels increased significantly in 20 hypertensive men after 6 months of therapy with indapamide, resulting in a significant fall of the low-density lipoprotein/high-density lipoprotein ratio, an atherogenic risk factor, regardless of preexisting lipid disorders.