An evaluation of potassium usage in ambulatory hypertensive patients.

Controversies surround the practice of prescribing potassium for ambulatory hypertensive patients who are being treated with diuretics. A chart review was conducted in a family medicine group practice to examine habits of potassium monitoring and supplement prescribing for patients receiving diuretic therapy for control of hypertension. Eighty-four percent of the 134 patients studied were monitored for serum potassium. For those with values obtained both before and after institution of diuretic therapy, mean potassium fell from 4.1 mEq/liter to 3.8 mEq/liter and 29 percent of patients had potassium levels fall to 3.5 mEq/liter or less. Almost half of patients received some type of potassium therapy, with diet enrichment and pharmacologic supplementation being the most common. When mean serum potassium values and percentage of patients with hypokalemia were compared for patients who were prescribed potassium therapy and for those who were not, there was little evidence that patients benefited from potassium prescribing.