An increased risk for occurrence of diabetic metabolic states has been reported for treatment with atypical antipsychotics. Initial studies suggest that atypical antipsychotics as a heterogeneous group of substances are not equally concerned. An increased risk for development of diabetes mellitus can be assumed for clozapine and olanzapine, while other atypical and conventional antipsychotics seem to carry only a slightly elevated risk. It remains as yet unresolved whether there is a causal connection or whether other not yet identified factors are involved. However, atypical antipsychotics intervene in various ways in glucose and fatty acid metabolism due to their broad receptor profile.We suggest that some atypical antipsychotics disturb regulatory loops of fat metabolism in fatty tissue and muscle,which may result in insulin resistance and finally diabetes. Changes in leptin release and development of leptin resistance possibly play an important role. These new results should be considered when planning therapy, although a final risk analysis is not yet possible.
