In this study, we are going to investigate quantitative and qualitative natures of appetite and eating-behavior changes induced by atypical antipsychotics, i.e., risperidone, olanzapine and aripiprazole, in schizophrenia patients.

This is an observational study. 2 Self-report questionnaires assessing changes of appetite and eating behaviors after medication are applied to patients who have been receiving one of the three atypical antipsychotics. We are going to compare changes of appetite and eating behaviors after medication between three atypical antipsychotics and investigate the association between changes of appetite and eating behaviors and changes of weight after medication.

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

outpatients clinic for schizophrenia