Background
Recent evidence regarding the multifactorial etiology of psychosis suggests that it can be trauma-induced. Therefore, there is a growing interest in using trauma-focused interventions to treat patients with psychosis and a history of traumatic events. Eye Movement Desensitization and Reprocessing (EMDR) is an approved, effective therapy for post-traumatic stress disorder (PTSD), but its use in the presence of psychotic features is still under scrutiny. 

Objectives
To assess the safety of EMDR in individuals with psychosis and co-morbid PTSD and evaluate its effectiveness in reducing psychotic and trauma-related symptoms.

Methods
Relevant randomized controlled trials (RCTs) were obtained from six databases using an extensive search strategy. Eligible studies were identified based on our inclusion and exclusion criteria, and then quality was assessed. Data was extracted from each study and narratively synthesized. 

Results
Four RCTs were included in our review, with an additional report for one. EMDR was generally superior to TAU and the WL condition in improving symptoms of psychosis and PTSD. It led to consistent improvements in clinician and patient-rated PTSD symptoms and was particularly effective in reducing psychotic negative symptoms (PANSS-N) and paranoid thinking (GPTS). However, improvements in delusions and auditory hallucinations (PSYRATS-D and AH) were mostly insignificant. No serious adverse events related to the therapy itself were reported in any of the trials.  

Conclusion
Overall, EMDR promises to be a safe and effective therapy in people with psychosis and PTSD. Large-scale trials with longer follow-up periods are needed to confirm our findings.