Compulsive water drinking in the setting of anticholinergic drug use: an unrecognized cause of chronic renal failure.

Compulsive water drinking (psychogenic polydipsia) is a well-recognized clinical entity that is often seen in individuals with psychiatric disorders, especially schizophrenia. Although urinary tract abnormalities including enlarged bladders and hydronephrosis have been reported, the presence of chronic renal failure is rarely reported in this disorder. We report four patients with psychogenic polydipsia who presented with chronic renal failure due to obstructive uropathy in the absence of demonstrable anatomic causes of obstruction. The likely mechanism of functional obstructive uropathy is bladder failure due to a combination of excessive water ingestion, enlarged bladder volumes, and use of anticholinergic medications.