The goal of antihypertensive therapy is to restore blood pressure to normal with as few side effects as possible. Usually this is best accomplished by skillfully combining two or more drugs in the regimen. A diuretic should be the cornerstone on which the regimen is built; for many patients with mild hypertension, a diuretic will be the only drug needed. Selection of drugs should be influenced by severity of hypertension and by the presence of complications and preexisting symptoms or conditions that, though unrelated to hypertension, might be aggravated by certain drugs. Combination tablets should be employed in selected patients only.
Gifford RW. Drug Combinations as Rational Antihypertensive Therapy. Arch Intern Med. 1974;133(6):1053-1057. doi:10.1001/archinte.1974.00320180171014