twice the risk for receiving a diagnosis of schizophrenia, while those who used chronically were at six times the risk compared to non-users [2]. Notably, the administration of intravenous THC in healthy individuals has been shown to directly induce psychotic symptoms, both self-reported and assessed by the Positive and Negatve Symptom Scale (PANSS) [32, 107]. Across multiple studies, cannabis use has been correlated with earlier onset of psychosis, increased symptom severity, higher rates of relapse and longer hospitalization time, as well as overall poorer illness and quality-of-life outcomes [33, 40, 54, 58, 79, 90, 99, 113, 145]. In one study, continued cannabis use following psychosis onset, when compared to discontinued use, was associated with higher rates of relapse, longer hospital admissions, enhanced positive and negative symptoms, as well as a variety of negative impacts on daily functioning [128]. Importantly, cannabis abstinence has been shown to ameliorate cognitive impairments related to cannabis use, such as verbal memory and learning, as well as specific symptomology (e.g. depression), suggesting that cannabis may contribute to symptom exacerbation in schizophrenia [116–118]. Interestingly, however, a recent trial by McGuire and colleagues suggests the potential of administering 1000 mg of cannabidiol (CBD) daily for 6 weeks alongside
