Antipsychotic medication: effects on regulation of glucose and lipids

Since the introduction of chlorpromazine in the 1950s, antipsychotics have been used for the treatment of schizophrenia. The phenothiazines were followed by the butyrophenones, particularly haloperidol. With all the movement disorder side effects of these medications (extrapyramidal syndrome, akathisia, tardive dyskinesia), the pharmaceutical industry has gradually released atypical antipsychotics. This class includes clozapine (released in the USA in 1990), risperidone (1994), olanzapine (1996), quetiapine (1998) and ziprasidone (2001). However, the rate of diabetes mellitus in patients with schizophrenia appeared to increase with the availability of this class of medications. In reviewing rate and degree of changes in weight, glucose control and lipid levels induced by typical and atypical antipsychotics, it was found that in contrast to case reports, there is a dearth of retrospective, open and controlled studies. However, in studies as early as 1964, significant weight increases were found to be associated with use of chlorpromazine. While the phenothiazines may have some effect on patients with chemical diabetes, there is little evidence of the typical antipsychotics producing diabetes mellitus de novo, or worsening diabetes that is already been discovered. Ziprasidone appears to be the antipsychotic with the most beneficial combination of effects: no weight gain, no change in glucose utilisation and reductions in cholesterol and serum triglycerides (TGs).