Polydipsia and tardive dyskinesia in chronic psychiatric patients--related disorders?

Dopamine supersensitivity, presumably playing a role in tardive dyskinesia, has been implicated in the unexplained polydipsia occurring in chronic psychiatric patients. To investigate this hypothesis, the authors compared laboratory measurements indicating the fluid status of 65 patients before and after the development of tardive dyskinesia. No evidence was found that patients who develop tardive dyskinesia concurrently develop abnormalities in fluid regulation.