Effects of Atypical Antipsychotics on Appetite and Eating Behavior of Schizophrenia Patients

Inclusion Criteria: 1. Patients meeting the DSM-IV criteria of schizophrenia, schizophreniform disorder, or schizoaffective disorder 2. Male and female patients aged 19\~59 3. Patients receiving monotherapy with one of the three AAPs, i.e., olanzapine, risperidone, and aripiprazole for more than two and less than 24 months 4. Patients who had at least one-week antipsychotics-free periods before starting the above antipsychotics 5. Clinically stable and able to complete the questionnaires 6. Patients who sufficiently understand the objective of the study and sign informed consent form Exclusion Criteria: 1. Patients having any medical illness or taking any medicine affecting appetite and body weight 2. Patients with severe and unstable medical, neurological or systemic illnesses 3. Patients having any comorbid psychiatric disorders including substance use disorders and eating disorders. 4. Pregnant or breast-feeding women