A 93 year-old hypertensive woman was found to have severe hypokalemia (as low as 1.3 mEq/L) and developed paralysis of the all extremities associated with metabolic alkalosis, hypoxemia, hypercapnea, extremely high levels of creatine phosphokinase (up to 9280 U/L), myoglobin and myoglobinuria compatible with rhabdomyolysis. Plasma renin activity and aldosterone levels were below normal. She was found to have been taking licorice-containing herbal medicines for the last 7 years. With the discontinuation of the licorice-containing medicines and administration of spironolactone together with intravenous and oral potassium supplement, her serum potassium level was normalized and her clinical symptoms and hypertension improved within 2 weeks.