Cannabidiol has recently been proposed as an antipsychotic for schizophrenia. However, its clinical use and safety is controversial. To answer this question, we used Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We identified six systematic reviews incorporating four primary studies overall, including two randomized trials. We extracted data from the systematic reviews, reanalyzed data from primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. We concluded cannabidiol probably does not improve symptoms in schizophrenia and leads to frequent side effects.