Psilocybin-assisted Treatment for Cannabis Use Disorder

Inclusion Criteria: * ≥ 18 years of age. * Capable of providing written informed consent for participation into the study. * Willingness to allow the study team to review past medical records. * Currently meets criteria for The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) diagnosis of Cannabis Use Disorder. * Be medically stable as determined by screening for medical problems via a personal interview, a medical questionnaire, a physical examination, an electrocardiogram (ECG), and routine medical blood and urinalysis laboratory tests. * Concurrent pharmacotherapy with selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), and/or bupropion is allowed if the type and frequency of the therapy has been stable for at least two months prior to screening. Allowable bupropion doses for participants will be ≤300mg/day. Exclusion Criteria: * Meeting DSM-5 criteria for another moderate or severe substance use disorder (excluding tobacco) within the past 5 years. * Currently taking antipsychotics, monoamine oxidase (MAO) inhibitors, or antidepressant medications other than SSRIs, SNRIs, or bupropion. Allowable bupropion doses for participants will be ≤300mg/day. * Currently taking lithium or other primary centrally-acting serotonergic medications, whether over-the-counter or prescription (e.g., efavirenz, 5-hydroxytryptophan, St. John's wort). * Cardiovascular conditions: angina, a clinically significant E…