<p>The Combination of these ingredients has an additive antihypertensive effect, reducing blood pressure to a greater degree than either component alone. This combination has mild vasodilating properties which reduces heart rate and blood pressure in hypertensive patients. Hydrochlorothiazide affects the renal tubular mechanisms of electrolyte reabsorption which directly increase the excretion of sodium and chloride in approximately equivalent amounts. The diuretic action of Hydrochlorothiazide reduces plasma volume, increases plasma renin activity and increases aldosterone secretion.</p>