A 78-year-old man was hospitalized because of muscular weakness and acute renal failure. He had been taking glycyrrhizin (280 mg/day) for the last 7 years. Hypertension was noted in his history. Serum potassium was 1.9 mEq/l with metabolic alkalosis. There was hyporeninemic hypoaldosteronism. Serum enzymes, including GOT, LDH and CPK were markedly elevated. In addition, serum myoglobin was as high as 46 micrograms/ml with massive myoglobinuria. Oliguria occurred and blood urea nitrogen and serum creatinine rapidly elevated from 20.9 to 87 mg/dl and from 1.3 to 6.7 mg/dl, respectively. Profound calcium deposition was found in the damaged skeletal muscles, including the quadriceps femoris, axillar, neck, and cardiac muscles. These results indicate that licorice-induced pseudoaldosteronism produces hypokalemic rhabdomyolysis, resulting in acute renal failure and profound deposition of calcium into the damaged skeletal and cardiac muscles.