Chronic cannabis use Mental and Behavioural Disorders Chronic cannabis use
Conditions
Interventions
All participants receive medical grade cannabidiol (CBD) formulated into capsules for oral administration. Each capsule contained 50mg of 99.9% pure CBD powder solved in corn oil gelatin capsules (BSP
Sponsors
University of Wollongong
Eligibility
Sex/Gender
All
Inclusion criteria
Inclusion criteria: 1. Cannabis use at least once per week for a minimum of three years 2. Between 18 and 55 years of age
Exclusion criteria
Exclusion criteria: 1. Current regular (more than once per month) use of substances other than cannabis, aside from alcohol and tobacco 2. Consumption of more than 28 standard drinks of alcohol per week 3. A history of regular illicit drug use (more than weekly) or dependence on or treatment seeking for any substance other than cannabis 4. Any neurological or psychiatric disorders (assessed by the MINI International Psychiatric Interview Plus) 5. Pregnancy of lack of contraception use for female cannabis users 6. Contraindications for EEG or MRI (e.g. epilepsy, metal implants, claustrophobia)
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| 1. Hippocampal volumetrics (whole hippocampus as well as subfields (e.g. CA1 and subiculum) is assessed by magnetic resonance imaging (MRI) using high resolution T1 weighted images at baseline and following 10 weeks of CBD administration 2. Markers of hippocampal neuronal integrity (NAA), as well as glutamate and GABA levels in the hippocampus, aremeasured using magnetic resonance spectroscopy (MRS) at baseline and following 10 weeks of CBD administration 3. MMN amplitude is recorded via electroencephalography (EEG) at baseline and following 10 weeks of CBD administration | — |
Secondary
| Measure | Time frame |
|---|---|
| 1. Other EEG and fMRI measures including P50 and resting state EEG/fMRI measured at baseline and following 10 weeks of CBD administration 2. Neuropsychological measures, assessed utilising the Rey Auditory Verbal Learning Test (RAVLT), and the Cambridge Neuropsychological Test Automated Battery (CANTAB) and CogState test batteries at baseline and following 10 weeks of CBD administration 4. Psychological symptomatology, as assessed by the Beck Depression Inventory (BDI); State-Trait Anxiety Index (STAI-I and II); Profile of Mood States (POMS); Community Assessment of Psychic Experiences (CAPE); Schizotypal Personality Questionnaire (SPQ); and Cannabis Experiences Questionnaire (CEQ) at baseline and following 10 weeks of CBD administration. 5. Substance use measures, utilising Timeline Follow Back; Cannabis Withdrawal Scale (CWS), Severity of Dependence Scale; and the Alcohol Use Disorder Identification Test (AUDIT) at baseline and following 10 weeks of CBD administration. 6. Levels of CBD and THC metabolites and neurotransmitter markers in blood and urine weekly throughout the 10 week trial | — |
Countries
Australia
Outcome results
None listed