Hyponatremia-associated rhabdomyolysis

Background: Hyponatremia is the most frequent electrolyte disorder. However , hyponatremia rarely results from excessive water intake, unless the kidne y is unable to excrete free water, such as in patients on thiazide diuretic s; in addition, hyponatremia is an uncommon cause of rhabdomyolysis. Method s: We present a 51-year-old hypertensive woman on chronic hydrochlorothiazi de therapy who developed acute water intoxication and severe myalgias. Resu lts: The patient developed acute hypotonic hyponatremia and subsequent rhab domyolysis. We discuss the mechanisms responsible far the development of hy ponatremia and its association with rhabdomyolysis. Conclusion: Muscle enzy mes should be monitored in patients with acute hyponatremia who develop mus cle pain, and hyponatremia-induced rhabdomyolysis must be considered in pat ients with myalgias receiving thiazide diuretics.