[Diuretics for therapy of patients with hypertension]

Diuretic agents have antihypertensive effects mainly be decreasing extracellular volume and cardiac output. These diuretics are described with regard to mechanism of action, site of action, adverse effects, and drug interactions. Thiazide diuretics inhibit the Na(+)-Cl- symporter in the distal convoluted tubule, by competing for the Cl- binding site, and increase Na+ and Cl- excretion. Loop diuretics are inhibitors of Na(+)-K(+)-2Cl- symporter in the thick ascending limb of the loop of Henle. However, loop diuretics are not the diuretic of first choice and should be reserved for patients in whom other diuretics or antihypertensive drugs do not result in a satisfactory response. The potassium sparing diuretics are used primarily to reduce the kaliuresis and potenciate the hypotensive effect of a thiazide.