[Diabetes mellitus after treatment with clozapine]

In a 40-year old patient with schizophrenia treated with sustained-action perfenazine for schizophrenia, diabetes mellitus type 2 and hypertension developed when clozapine was added to the regimen. The blood sugar values and the blood pressure normalized when clozapine was discontinued two weeks later. When he was 44 years old, clozapine was resumed as the psychotic symptoms did not subside. Diabetes mellitus reappeared and did not disappear after discontinuation of the clozapine. Insulin therapy was necessary. An association between the emergence of diabetes mellitus and the use of clozapine is suggested. Previously 15 cases of diabetes mellitus emerging during treatment with clozapine were described in the international literature. Monitoring of blood glucose is advised in patients with a positive family history of diabetes mellitus or with a personal history of impaired glucose tolerance.