Functional obstructive uropathy: a significant factor in the hyponatremia of psychogenic polydipsia?

A case is presented of psychogenic polydipsia with hyponatremia. Prolonged observation of the patient revealed that episodes of hyponatremia correlated best with bladder failure and were promptly corrected by bladder catheterization. Bladder catheterization for underlying functional obstructive uropathy should be considered early in the treatment of patients with psychogenic polydipsia and hyponatremia.