Medicinal Cannabis Prescription Before an Inpatient Psychiatric Admission: A Retrospective Observational Audit.
Nikki Bodnar, Timothy Tanzer, Lesley Smith, Fehim Puris, Karl Winckel
Journal of Psychiatric Practice March 1, 2026 DOI: 10.1097/pra.0000000000000907 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Retrospective observational audit Peer reviewed |
|---|---|
| Sample size | 752 |
| Population | Adult patients admitted to a large metropolitan adult acute psychiatric unit in Brisbane, Australia, between September 2021 and October 2023 |
| Duration | Prescriptions in the 90 days before admission; admissions between September 2021 and October 2023 |
| Topics | Cannabis |
| Keywords | Delta-9-Tetrahydrocannabinol THC Hospitalization Medicinal cannabis Psychosis Serious mental illness |
| Key findings | Of 752 psychiatric inpatients screened, 35 (4.7%) had received medicinal cannabis prescriptions in the 90 days before admission; 97.1% of these involved THC-containing products (mean THC concentration 24%), anxiety was the leading indication (48.6%), and 88.6% were admitted with psychosis. The authors characterize this as a small but clinically important proportion of patients vulnerable to psychosis. |
Abstract
Prescribing of medicinal cannabis has expanded in Australia; however, evidence for benefit in psychiatric populations is limited. The goal of this study was to estimate the prevalence and characteristics of recent medicinal cannabis prescribing among psychiatric inpatients and to describe presentations associated with these admissions. We conducted a retrospective observational audit of adult patients admitted to a large metropolitan adult acute psychiatric unit in Brisbane, Australia, between September 2021 and October 2023. Electronic medical records were reviewed to identify medicinal cannabis prescriptions in the 90 days before admission. Information concerning demographics, indications, formulation, labeled potency, dispensing frequency, presentations, and length of stay were extracted for patients who had received such prescriptions. Of the 752 patients who were screened, 35 patients (4.7%) were prescribed medicinal cannabis in the 90 days before admission. Most of the patients (91.4%) who had been prescribed medicinal cannabis had a prior psychiatric diagnosis. The leading indication for the prescribed medicinal cannabis was anxiety (48.6%). Nearly all of the patients who were prescribed medicinal cannabis (97.1%) were prescribed at least one product containing delta-9-tetrahydrocannabinol (THC), with a mean THC concentration of 24%. The majority of patients prescribed medicinal cannabis (88.6%) were admitted with psychosis. A small but clinically important proportion of psychiatric inpatients vulnerable to psychosis had recent prescriptions for medicinal cannabis, predominantly for higher-potency THC-containing products. Product type, labeled potency, and timing of the last dispensing should be documented in routine psychiatric assessment. Further work clarifying the risks and benefits of cannabis prescribing in this population is required.
Comparable studies
Other observational and cohort studies on cannabis, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| High-potency cannabis and the risk of psychosis People with first episode of psychosis and healthy controls from the local population | 2009 | Case-control study | n = 454 |
| Ayahuasca-Assisted Therapy for Addiction: Results from a Preliminary Observational Study in Canada Rural aboriginal population | 2013 | Observational study | |
| Impaired cognitive performance in drug free users of recreational ecstasy (MDMA) Otherwise healthy young people | 2000 | Observational | |
| Continued cannabis use and risk of incidence and persistence of psychotic symptoms: 10 year follow-up cohort study Individuals from the general population in Germany aged 14-24 at baseline | 2011 | Observational cohort | n = 1,923 |
| Cannabis-induced psychosis and subsequent schizophrenia-spectrum disorders: follow-up study of 535 incident cases Patients treated for cannabis-induced psychotic symptoms in Denmark between 1994 and... | 2005 | Observational cohort | n = 535 |