Importance of oral glucose tolerance test in patient with schizophrenia.

We describe the case of a 39-year-old patient with schizophrenia who developed worsening of glucose metabolism during treatment with two different atypical antipsychotics, clozapine and quetiapine. Diabetes mellitus was recognized during clozapine treatment. During quetiapine treatment, while patient was taking diabetic diet, fasting and 1-hour glucose levels and body mass index, decreased, but 2-hour glucose levels increased.