Spurious Elevation of Urinary Catecholamines During Therapy with Alpha-Methyl-Dopa

Abstract
REFINEMENTS in techniques for the diagnosis of various forms of secondary hypertension and the introduction of effective hypotensive drugs have brightened the outlook for the hypertensive patient, but have compounded the problems of the physician. He must become increasingly aware of and wary of the possibility that the drugs which he is administering may spuriously influence the results of clinical tests on which the decision for surgical intervention may depend. For example, therapy with thiazide diuretics is frequently accompanied by hypokalemia that may be profound enough to cause the physician to suspect primary aldosteronism. Low sodium diets, sometimes employed in the treatment of hypertension, can cause an increase in the urinary excretion of aldosterone and, in certain circumstances, this too might lead to the erroneous diagnosis of primary aldosteronism. It has been shown that treatment with most of the antihypertensive drugs presently available may cause falsely positive or falsely negative