TREATMENT OF POLYDIPSIA AND HYPONATREMIA IN PSYCHIATRIC-PATIENTS - CAN CLOZAPINE BE A NEW OPTION

Polydipsia occurs frequently in chronic schizophrenic patients, some o f whom develop intermittent hyponatremia. Most therapeutic efforts hav e tried to control the hyponatremia. Four schizophrenic patients, foll owed for more than one year, showed improvement on clozapine. Case 1 w as an outpatient without history of hyponatremia who improved from pol ydipsia and psychosis. The last three were inpatients with polydipsia, intermittent hyponatremia, and psychosis who showed minimal improveme nt of psychosis but significant decrease in polydipsia and wafer intox ication. Case 2 relapsed to polydipsia when clozapine was discontinued on two occasions. Case 3 demonstrated polyuria during 39% of days bef ore clozapine and in 0% of days after two weeks of clozapine. In case 4, most baseline sodium levels were abnormal, but all became normal af ter clozapine. A rime-series analysis for intervention effects showed a significant effect of clozapine (p = .017). The limited information provided by these case reports suggest the need for controlled studies of the clozapine effect on polydipsic patients.