Is glycyrrhizin sensitivity increased in anorexia nervosa and should licorice be avoided? Case report and review of the literature

ObjectiveHypokalemia is a potentially life-threatening electrolyte disturbance in anorexia nervosa and is most frequently caused by purging behavior. We report a case of severe hypokalemia in anorexia nervosa induced by daily ingestion of approximately 20 g of licorice.MethodsTo confirm the diagnosis of licorice-induced pseudohyperaldosteronism, a re-exposure trial was performed.ResultsCessation of the licorice intake normalized plasma potassium, renin, and aldosterone levels and the urine cortisol/cortisone ratio. Re-exposure confirmed the diagnosis. The pronounced response to a relatively low daily dose of licorice suggests high glycyrrhizin sensitivity.ConclusionPatients with anorexia nervosa not only have decreased food intake but also selective and sometimes bizarre eating habits that, in association with increased sensitivity to glycyrrhizin, may cause severe hypokalemia.