Use of diuretics in hypertension

Antihypertensive monotherapy with diuretics renders blood pressure values in a large percentage of patients suffering essential hypertension and it reduces cardiovascular morbidity and mortality. Diuretics are effective in adult and elderly hypertensive subjects, independently of their ethnic group. Treatments with high doses of antihypertensive diuretics, such as 25 to 50 mg hydrochlorothiazide once daily, raise plasma renin activity, decrease plasma levels of potassium and magnesium and cause untoward changes in carbohydrate metabolism and the plasma lipid profile. These changes appear to limit the positive response on cardiovascular prognosis to antihypertensive therapy with classic diuretic doses. Lower doses of diuretics reduce high blood pressure to the extent in many patients and they may not produce unfavorable neuroendocrine and metabolic changes. Thiazide diuretics constitute the first group of diuretics used to treat uncomplicated hypertension, later appear drugs inhibiting the transportation of sodium in the Helen's loop with a more effective natriuretic action and they can be used specially in patients with renal insufficiency and heart failure. The third groups of diuretics are represented by potassium-sparing agents, usually given in combination with thiazyde diuretics. The fourth groups of diuretics are the selective aldosterone receptor blockers.