Patients with acute adrenal insufficiency may have musculoskeletal symptoms including flexion contractures, myopathy and hyperkalaemic neuromyopathy. However, the association between rhabdomyolysis and acute adrenal insufficiency is extremely rare and has only been reported infrequently in the literature. Hyponatraemia is often present in association with acute adrenal insufficiency complicated by rhabdomyolysis. We herein report the case of a patient with acute primary adrenal insufficiency and severe hyponatraemia complicated by rhabdomyolysis and acute kidney injury.