To report a case of recurrent hyponatremia and rhabdomyolysis in a teenager with psychogenic polydipsia.Case Summary
A 16-year-old boy was admitted with recurrent episodes of hyponatremia and rhabdomyolysis secondary to psychogenic polydipsia. He was treated with hypertonic saline, intravenous fluids, and supportive care.Discussion
Psychogenic polydipsia is a condition characterized by compulsive drinking. Severe hyponatremia is a rare, but serious complication in patients with psychogenic polydipsia. Failure in cell volume regulatory mechanisms, defective osmoregulation, defective urinary dilution, and enhanced secretion of vasopressin are believed to play a role in the development of hyponatremia. Rhabdomyolysis can complicate severe hyponatremia, although the exact mechanism is not known. Antipsychotic drugs are also implicated in rhabdomyolysis.Conclusions
Severe hyponatremia and rhabdomyolysis can complicate psychogenic polydipsia. Patients receiving antipsychotic drugs with concomitant severe hyponatremia need to be monitored for rhabdomyolysis.