[Risperidone and carbamazepine-induced syndrome of inappropriate antidiuretic hormone secretion: case study]

The inappropriate antidiuretic hormone secretion Syndrome (ADHS) accounts for approximately 50% of all diagnosed cases of hyponatremia while drug-induced ADHS accounts for a small proportion of cases. We report the case of a female patient, treated for schizoaffective disorder, who developed ADHS following the initiation of risperidone and carbamazepine. Biochemical test results suggested risperidone and carbamazepine-induced ADHS. The patient was successfully treated by stopping drug use and by fluid restriction. After correcting the serum sodium levels, the patient was treated with clozapine. She is currently on clozapine 400mg with stable serum sodium rates. Psychiatrists should be aware of the risk of severe hyponatremia associated with psychotropic drug use. It is therefore essential to monitor electrolyte levels, in particular sodium levels, in patients taking antipsychotics and anticonvulsants.