Fixed-dose combination antihypertensive drugs. Do they have a role in rational therapy?

Fixed-dose combination antihypertensive therapy has been available for over 25 years. During that time, considerable progress has been made in the development of physiologically appropriate combinations. The inherent advantage of fixed-dose combination therapy resides in its improving compliance because fewer pills are required. Alternatively, fixed-dose combination therapy limits dosage flexibility and dose titration of a single component of the combination to complement ongoing treatment of a concomitant non-hypertensive illness. The most frequently employed fixed-dose combinations include some form of a thiazide diuretic together with either a potassium-sparing diuretic, beta-blocker or an angiotensin converting enzyme inhibitor. Newer combinations using a calcium channel blocker and beta-blocker, or a calcium channel blocker and an angiotensin converting enzyme inhibitor are either in development or soon to be available. Such developments, if combined with appropriate cost reductions will ultimately increase the popularity of these combination drug administration strategies.