title: Does adding a second antipsychotic to clozapine improve clinical response in resistant schizophrenia?
abstract: Clozapine constitutes the treatment of choice in patients with schizophrenia with persisting symptoms despite antipsychotics at adequate dose and treatment duration. However, an important proportion does not respond to optimal doses of clozapine, so the addition of a second antipsychotic might increase clinical response. Searching in Epistemonikos database, which is maintained by screening multiple databases, we identified 17 systematic reviews comprising 62 studies addressing the question of this article, including 26 randomized trials. We combined the evidence using meta-analysis and generated a summary of findings following the GRADE approach. We concluded adding a second antipsychotic to clozapine in patients with refractory schizophrenia probably leads to little or no difference in clinical response, and increases adverse effects.
authors.affiliation: Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile; Proyecto Epistemonikos, Santiago, Chile. Address: Facultad de Medicina, Pontificia Universidad Católica de Chile, Diagonal Paraguay 476, Santiago Centro, Chile. Email: daceituno@med.puc.cl.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Jiménez-Cornejo
authors.affiliation: Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile; Proyecto Epistemonikos, Santiago, Chile.
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Munizaga
authors.affiliation: Proyecto Epistemonikos, Santiago, Chile; Departamento de Psiquiatría, Facultad de Medicina, Pontificia Universidad Católica de Chile.
authors.forename: David
authors.initials: D
authors.lastname: Aceituno
mesh_terms: D014150:Antipsychotic Agents / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D003024:Clozapine / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D004351:Drug Resistance; D004359:Drug Therapy, Combination; D006801:Humans; D016032:Randomized Controlled Trials as Topic; D012559:Schizophrenia / Q000188:drug therapy* / Q000503:physiopathology; D016896:Treatment Outcome
chemical_list: D014150:Antipsychotic Agents; D003024:Clozapine