BEHAVIORAL TREATMENT OF PSYCHOGENIC POLYDIPSIA RICHARD J. MCNALLY University of Health Sciences/The Chicago Medical School and JOHN E. CALAMARI, PATRICIA M. HANSEN and CARLENE KALIHER Waukegan Developmental Ccntcr zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQP Summary -This report describes the behavioral trcatmcnt of psychogenic polydipsia in an autistic, severely mentally retarded woman who had a htstory of self-induced water intoxica- tion. Treatment emphasized the use of edibles and reductions in activity demands to reward water refusal. Emploving this procedure. paraprofessional staff normalized the client’s water consumption. and thereby prevented further episodes of potentially-fatal water intoxication. Psychogenic polydipsia refers to water drinking that greatly surpasses physiological require- ments (Webb and Gehi, 1981). If fluid intake exceeds the individual’s capacity for excre- tion, then the resultant hyponatremia may pro- duce signs of water intoxication including vomiting. agitation. ataxia, seizures, and coma (Rosenbaum et al., 1979). Water intoxication is potentially dangerous; three fatalities have been reported (Raskind, 1974; Rendell et al., 1978). Polydipsia-induced water intoxication occurs primarily in schizophrenics (Jos and Perez- Cruet, 1979), but occasionally occurs in psychotic depressives as well (Raskind ef al.. 1975). Polydipsia is associated with delusions in some cases (e.g. washing out sin); in others, the individual merely complains of great thirst. In a study involving 2.201 psychiatric patients. Jos et al. (1986) obtained lifetime prevalence rates for polydipsia and water in- toxication of 6.2 and 1.5%. respectively. Thus 25% of the polydipsic patients also had epi- sodes of intoxication. Of those who became in- toxicated. 85% were schizophrenic. Medical treatment for water intoxication involves restoration of electrolyte balance (e.g. Devereaux and McCormick, 1972). Regular administration of oral sodium may reduce the likelihood of seizures in polydipsic individuals (Vieweg et al.. 1985), and demeclocycline, a tetracycline derivative, may reduce the fre- quency and severity of intoxication in persons who also exhibit the syndrome of inappro- priate secretion of the antidiuretic hormone. vasopressin (SIADH; Nixon zyxwvutsrqponmlkjihgfedcba et al., 1952). Demeclocycline inhibits vasopressin’s anti- diuretic effects at the renal tubule. Not all water intoxication episodes, however. are due to this medical condition. Most interventions described in the litera- ture concern either the medical treatment or the prevention of water intoxication; few re- ports concern treatment of polydipsia, per se. Although psychopharmacological treatment of the underlying psychosis has led to remission of polydipsia in some cases (e.g. Raskind et al.. 1975), many chronic schizophrenics continue to drink water excessively even in the absence of florid psychosis. The only published account Requests for reprints should be addressed to Richard J. McNally. Dept of Psychology. University of Health Sciences/ The Chicago Medical School. Bldg. 51. North Chicago, IL 60064. U.S.A.