Rational diuretic management in congestive heart failure: a case-based review.

The pharmacology and pharmacokinetics of diuretics are unique among therapeutic drugs. Knowledge of these principles can be used to great advantage in the management of heart failure, whereas ignoring them can lead to either minor or life-threatening adverse consequences. Two major categories of potential therapeutic problems are diuretic resistance and the development of disturbances in serum potassium and other electrolytes. Inhibition of sodium reabsorption in the loop of Henle or distal convoluted tubule leads to renal potassium wasting, whereas inhibition of sodium reabsorption in the collecting duct (either directly, as with triamterene or amiloride, or through aldosterone antagonism) causes potassium retention. Combining diuretics of different classes, a rational and frequently used strategy to counter diuretic resistance, can be anticipated to balance or magnify these effects, depending on the site of action of the individual drugs.