Licorice-induced hypokalemic myopathy and hypokalemic renal tubular damagein anorexia nervosa

A patient with a history of anorexia nervosa developed licorice-induced hyp okalemic myopathy. With potassium replacement, high CPK blood level and myo pathic signs returned to normal. However, the patient manifested persistent hypokalemia and impaired renal function to concentrate and acidify the uri ne. renal biopsy demonstrated intense degeneration and vacuolation of tubul es with a normal glomerus which was consistent with hypokalemic nephropathy . Prolonged hypokalemia in anorexia nervosa is sometimes attributed to surr eptitious purging or taking diuretics, but it is necessary to check the uri ne pH, the urine-specific gravity, and the urine potassium level in order t o find underlying renal damage even after hypokalemic myopathy is treated s uccessfully. (C) 1999 by John Wiley & Sons, Inc.