Although CB1R antagonists are not licensed owing to adverse effects,64 they have been found to reduce deficits induced by a phencyclidine model of psychosis.65 However, CB1R-negative allosteric modulators (eg, cannabidiol) are associated with few adverse effects66 and have been shown to reduce CB1R agonist efficacy and potency, preventing CB1R internalization.67 Taken together, these results support further work to explore the therapeutic potential of CB1R modulators in schizophrenia. The gene discussed is CNR1; the disease is psychotic disorder.