Potassium supplements in patients receiving long-term diuretics for oedema.

Plasma, blood cell, and total body potassium levels were measured serially in 21 patients receiving long-term diuretics for the treatment of cardiac oedema and the results compared with similar measurements in 10 control subjects. Initially, all diuretic recipients received potassium chloride supplements. However, in 17 of the 21 subjects these were discontinued and measurements of potassium status were repeated regularly thereafter. No significant fall in the measured indicators of potassium status were observed in the patients in whom potassium was withdrawn; however, in one subject with persistent cardiac failure who presented with hypokalaemia this was not corrected even after intensive potassium supplementation. It is concluded that for those taking a normal diet who are free of any major gastro-intestinal disorder, routine potassium supplementation is unnecessary, and might indeed occasionally prove harmful.