Spironolactone should not be used in patients with hyperkalemia or severe renal impairment. It should be used with care in patients who are at increased risk of developing hyperkalemia; such patients include the elderly those with diabetes mellitus and those with some degree of renal or hepatic impairment. It should also be given with care to patients likely to develop acidosis. Serum electrolytes and blood-urea-nitrogen should be measured periodically.