A Case of Diabetic Ketoacidosis Associated with Risperidone Treatment

Abstract
The association between schizophrenia and diabetes has been previously documented. Case reports have also demonstrated that initiation of atypical antipsychotic agents may induce or exacerbate diabetes mellitus. A 26-year-old man without a family history of diabetes mellitus presented with deep coma after 5 months of treatment with risperidone. He was diagnosed with diabetic ketoacidosis, was given insulin and saline infusion, and his antipsychotic agent was changed from risperidone to ziprasidone. Insulin therapy and oral agent was discontinued within two months of follow-up. The rapid onset of diabetes, and the disappearance of hyperglycemia after discontinuation of the drug suggested that risperidone had been a factor in his diabetic ketoacidosis. During three years of subsequent follow-up, testing revealed no evidence of elevated serum glucose levels or impaired glucose tolerance. In our opinion psychiatrists should routinely ask patients treated with antipsychotic agents such as risperidone for diabetic symptoms, weight loss, lethargy, polydipsia and/or polyuria, and monitor serum glucose levels. Although there is no consensus on the best way to switch from one antipsychotic drug to another, for those patients who develop diabetes during therapy with risperidone a change to ziprasidone treatment may maintain normal glucose levels.