Patients with schizophrenia are much more likely to be engaged in smoking and other addictive behaviors, possibly related to biochemical abnormalities in the reward center of the brain. The primary purpose of the present study is to investigate whether switching patients with schizophrenia to a new atypical antipsychotic, aripiprazole, a drug with a novel mechanism of action, will have an impact on smoking behavior.

This is an 8 week open label trial being conducted in stable adult outpatients with schizophrenia who are smokers. The primary intervention is a switch in the subject's antipsychotic to aripiprazole, flexibly dosed between 15-30 mg/day. The outcome measures include a rating of smoking behavior using the Fagerstrom Test for Nicotine Dependence, and saliva cotinine obtained at baseline and endpoint. Secondary measures include weight, serum glucose and lipids, rating of symptom severity using the PANSS, and both ratings and instrumental measures of motor functioning. We anticipate enrolling up to 25 subjects to obtain the needed 15 completers at the week 8 endpoint.

Inclusion Criteria:

1. Schizophrenia, on stable antipsychotic dose for at least one month
2. Ages 18-65 inclusive
3. Overweight (body mass index of 25 kg/m2 or greater)
4. Daily cigarette smoker (by self-report)

Exclusion Criteria:

1. Inability to provide informed consent
2. Treatment refractory schizophrenia
3. Current treatment with clozapine
4. Current antipsychotic polypharmacy which may preclude monotherapy with aripiprazole
5. Documented poor compliance with oral antipsychotic medication