Jonathan A Pushpa-Rajah1, Benjamin C McLoughlin2, Donna Gillies3, John Rathbone4, Hannele Variend5, Eliana Kalakouti6, Katerina Kyprianou6. 1. Queens Medical Centre, School of Medicine, The University of Nottingham, Nottinghamshire, UK; Pushpa-Rajah and Benjamin Mcloughin were co-lead authors. mzyjp3@nottingham.ac.uk. 2. Queens Medical Centre, School of Medicine, The University of Nottingham, Nottinghamshire, UK; Pushpa-Rajah and Benjamin Mcloughin were co-lead authors. 3. Western Sydney Local Health District-Mental Health, Parramatta, Australia; 4. Faculty of Health Sciences and Medicine, Bond University, Gold Coast, Australia; 5. Becklin Centre, CRHT, Leeds, UK; 6. Department of Medicine, University of Nottingham, Nottingham, UK;
Abstract
BACKGROUND: Many people with schizophrenia smoke cannabis, and it is unclear why a large proportion do so and if the effects are harmful or beneficial. It is also unclear what the best method is to allow people with schizophrenia to alter their cannabis intake. OBJECTIVES: To assess the effects of specific psychological treatments for cannabis reduction in people with schizophrenia. To assess the effects of antipsychotics for cannabis reduction in people with schizophrenia. To assess the effects of cannabinoids (cannabis-related chemical compounds derived from cannabis or manufactured) for symptom reduction in people with schizophrenia. SEARCH METHODS: We searched the Cochrane Schizophrenia Group Trials Register (August 2013) and all references of articles selected for further relevant trials. We contacted the first author of included studies for unpublished trials or data. SELECTION CRITERIA: We included all randomized controlled trials involving cannabinoids and schizophrenia/schizophrenia-like illnesses, which assessed: (1) treatments to reduce cannabis use in people with schizophrenia and (2) the effects of cannabinoids on people with schizophrenia. CONCLUSIONS: Results are limited and inconclusive due to the small number and size of randomized controlled trials available and quality of data reporting within these trials. Currently, there is no evidence to demonstrate that one type of adjunct psychological therapy or one type of drug therapy is more effective than another. There is also insufficient evidence to show that cannabidiol has an antipsychotic effect.
BACKGROUND: Many people with schizophrenia smoke cannabis, and it is unclear why a large proportion do so and if the effects are harmful or beneficial. It is also unclear what the best method is to allow people with schizophrenia to alter their cannabis intake. OBJECTIVES: To assess the effects of specific psychological treatments for cannabis reduction in people with schizophrenia. To assess the effects of antipsychotics for cannabis reduction in people with schizophrenia. To assess the effects of cannabinoids (cannabis-related chemical compounds derived from cannabis or manufactured) for symptom reduction in people with schizophrenia. SEARCH METHODS: We searched the Cochrane Schizophrenia Group Trials Register (August 2013) and all references of articles selected for further relevant trials. We contacted the first author of included studies for unpublished trials or data. SELECTION CRITERIA: We included all randomized controlled trials involving cannabinoids and schizophrenia/schizophrenia-like illnesses, which assessed: (1) treatments to reduce cannabis use in people with schizophrenia and (2) the effects of cannabinoids on people with schizophrenia. CONCLUSIONS: Results are limited and inconclusive due to the small number and size of randomized controlled trials available and quality of data reporting within these trials. Currently, there is no evidence to demonstrate that one type of adjunct psychological therapy or one type of drug therapy is more effective than another. There is also insufficient evidence to show that cannabidiol has an antipsychotic effect.
Authors: Benjamin C McLoughlin; Jonathan A Pushpa-Rajah; Donna Gillies; John Rathbone; Hannele Variend; Eliana Kalakouti; Katerina Kyprianou Journal: Cochrane Database Syst Rev Date: 2014-10-14