During the first month after removal of a unilateral aldosterone-producing adenoma, sodium conservation is poor and restriction of sodium intake may result in adrenal insufficiency. The excretion of aldosterone is reduced and does not increase in response to stimulation by administration of corticotropin, angiotensin, and by restriction of sodium intake. Chronic hypervolemia in patients with primary aldosteronism can result in selective suppression of the ability of the adrenal gland to secrete normal amounts of aldosterone immediately after removal of an aldosterone-secreting tumor.