Smoking and therapeutic response to clozapine in patients with schizophrenia

Background: Of patients with schizophrenia, 70 to 80% smoke. Nicotine corre cts certain information processing and cognitive psychomotor deficits seen in many patients with schizophrenia. Clozapine, but not conventional antips ychotics, has been shown to correct some of these deficits. Methods: We assessed psychopathology and smoking in 70 patients with treatm ent refractory schizophrenia (55 smokers and IS nonsmokers) at baseline whe n they were receiving conventional antipsychotics and again after they were switched to clozapine. Results: Smokers showed significantly greater therapeutic response to cloza pine than nonsmokers. Smokers smoked less when treated with clozapine than when treated with conventional antipsychotics. Conclusions: Certain patients with schizophrenia have contributing pathophy siologic mechanisms that respond favorably to either nicotine or clozapine, (C) 1999 Society of Biological Psychiatry.