The occurrence of hypokalemia in association with high blood pressure is suggestive of primary hypermineralocorticism since in this case both abnormalities might result from a single mechanism. However, adrenal adenomas is well as the various forms of adrenal hyperplasia appear to be quite uncommon, whereas a number of other causes of potassium depletion are far more prevalent and may be associated with essential hypertension. The demonstration of the precise mechanism of both decreased serum potassium and increased blood pressure is a prerequisite for a successful treatment.