We report the case of a 61-year-old man who was referred to our Institution because of severe hypokalemia, rhabdomyolysis and high blood pressure. Severe hypokalemia may lead to rhabdomyolysis. The plasma aldosterone concentrations were low and the plasma renin activity was suppressed. A diagnosis of apparent mineralocorticoid excess, attributable to licorice and grapefruit juice ingestion, was made. Glycyrrhizic acid and glycyrrhetinic acid, its hydrolytic product, in licorice extracts, and polyphenols, in grapefruit juice, can inhibit 11 beta-hydroxysteroid dehydrogenase type 2, the enzyme that converts cortisol to cortisone. Moreover, having suspended licorice and grapefruit juice ingestion, the plasma K+ levels and blood pressure values progressively and simultaneously returned to normal. We would like to stress the diagnostic weight of a careful history taking.