A Four-week Clinical Trial Investigating Efficacy and Safety of Cannabidiol As a Treatment for Acutely Ill Schizophrenic Patients

Schizophrenia is a heterogeneous mental disorder that affects one percent of the world's population. Current antipsychotics are only partially effective, and their use is often associated with serious side effects. Cannabidiol is a natural counterpart of the psychoactive component of marijuana, delta-9-tetrahydrocannabinol. While cannabidiol has no psychotomimetic or addictive properties, it indirectly affects endogenous cannabinoid signalling by impairing the degradation of the endocannabinoid anandamide. In a controlled clinical trial of cannabidiol versus amisulpride (an established antipsychotic) in acute paranoid schizophrenics the investigators showed a significant clinical improvement in all symptoms of schizophrenia compared to baseline with either treatment. But cannabidiol displayed a significantly superior side-effect profile. This study is to evaluate the efficacy and safety of this novel treatment option in comparison to placebo and olanzapine, an established second generation antipsychotic in the treatment of acute schizophrenia and schizophrenia maintenance therapy, in a four-week clinical trial.