Evaluation of the Necessity of Long-term Pharmacological Treatment With Antipsychotics in Schizophrenic Patients

The main objective of the trial is to evaluate for the first time, how long an antipsychotic relapse-prevention should be continued and to which time a patient is protected enough, so that a guided withdrawal or reduction of the medication seems appropriate. Relapse is defined as primary outcome. We include patients with schizophrenia or schizoaffective disorder in remission for at least 3 years under a stable antipsychotic medication.

Inclusion criteria

• Diagnosis of schizophrenia or schizoaffective disorder
• The participants have to be in remission for at least 3 years (i.e. no psychiatric hospitalisation) under a stable antipsychotic medication. Remission will be measured using the remission criteria by Andreasen et al. (2005) Score ≤3 for the items concerning psychosis of the "Positive and Negative Syndrom Scale" (PANSS; Kay et al., 1987): "Delusions" (P1), "Conceptual disorganisation" (P2), "Halluzinations" (P3), "Mannerisms and posturing" (G5) and "Unusual thought content" (G9) and a score ≤3 on the "Clinical Global Impression Severity Scale" (CGI-S; Guy, 1976)
• Able to give informed consent

Exclusion criteria

• Actively suicidal
• Serious medical illnesses
• Known non-complience concerning the medication
• Medication with clozapin
• Medication with antidepressants and mood stabilisors that were initiated during the last 6 weeks before study enrollment
• Patients with substance dependence other than nicotine or caffeine within 6 months prior to baseline
• Unability to give informed consent
• Pregnancy