Brain metabolism in patients with schizophrenia before and after acute neuroleptic administration

Positron emission tomography (PET) with 11C-2-deoxyglucose (11DG) was used to compare regional brain metabolism in four patients with chronic schizophrenia who had no history of psychotropic medication and in 12 normal controls. Patients had a second PET scan after an injection of thiothixene to evaluate the effects of acute neuroleptics on glucose metabolism. The patients showed higher glucose metabolic values than the normals and did not show the metabolic hypofrontality reported in chronic medicated patients with schizophrenia. Administration of the neuroleptic did not have a significant effect in the metabolic pattern of the patients. These results give support to the hypothesis that prolonged medication may contribute to the metabolic hypofrontal pattern seen in patients with schizophrenia.