Effect of propranolol on total exchangeable body potassium and total exchangeable body sodium in essential hypertension.

Total exchangeable body potassium (KE) was determined in fifteen patients with essential hypertension, and total exchangeable body sodium (NaE) in ten, before and after propranolol administration for 2-3 months. Blood pressure was reduced; serum potassium increased, but KE was unchanged. Serum sodium and NaE were unaffected during therapy. It is concluded that the increase in serum potassium during propranolol treatment could not be attributed to potassium retention, but is possibly due to a displacement from the intra- to the extracellular fluid compartment. The antihypertensive effect of propranolol could not be related to changes in NaE.