Double blind, randomised, placebo controlled trial of Sativex for the management of cannabis withdrawal

INTERVENTION: Investigational drug: Sativex (1 spray: 2.7 mg THC and 2.5 mg CBD) in an alcohol and peppermint oil liquid administered as an oromucosal spray onto the inside of the mouth (but not intended to be swallowed and digested through the stomach ‐ so some time (1 minute) should be taken after each single spray is administered to ensure absorption, before the next spray is administered). The patient cannot choose when they receive their 8 spray dose, they must have them all at the 6 hourly interval. Dosage form/strength: maximum 800 uL every six hours (X8 sprays every six hours). Participants may not take partial doses (i.e. 6 sprays) but they can ask to miss up to two of the 6 hourly dose in a day. Patients are in hospital for 8 nights, discharging on day 9. CONDITION: Cannabis withdrawal PRIMARY OUTCOME: Adverse events during the inpatient treatment period using a tailor made Adverse Events Checklist and administered by clinician/nurse/medical officer. Adverse events may include any of the following: Dizziness, Dry mouth, Tachycardia, Stomache ache, Slowed motor skills, slowed reaction time, anxiety, dysphoria, paranoia, oro‐mucosal ulceration. Adverse events will be rated on a 0 ‐ 3 scale, 0 being None, 1 being Mild, 2 being Moderate, 3 being Severe. Self‐reported measures of cannabis withdrawal using the Cannabis Withdrawal Scale (a modified version of the MWC (Budney et al., 1999)). Treatment completion, defined as completing 9 days of inpatient treatment under protocol conditions (categorical yes/no); and number of days of inpatient treatment completed (range: 0‐9). SECONDARY OUTCOME: Anxiety Sensitivity Index Blood plasma profiles of cannabinoid metabolites (THC and its primary metabolite (THC‐COOH) to CBD and its primary metabolite (CBD‐7‐oic acid)) Brief Treatment Outcome Measure‐Social Functioning Scale (Lawrinson, Copeland, & Indig, 2005) Cannabis Dependence using the Severity of Dependence Scale (SDS) (Martin, Copeland, Gates, & Gilmour, 2006; Swift, Copeland, & Hall, 1998) Cannabis Problems Questionnaire (Copeland, Gilmour, Gates, & Swift, 2005) Depression, Anxiety and Stress measures using the 21 item version of the Depression, Anxiety and Stress Scale (Lovibond & Lovibond, 1995) Distress tolerance Scale Insomnia severity index (Bastien, Vallieres, & Morin, 2001) Quality of life using the Sheehan Disability Scale Self efficacy for Quitting Cannabis Questionnaire Self‐reported cannabis use with total days used cannabis (range 0‐28) and longest period of continuous abstinence (range 0‐28) during the one month follow‐up period (quantifying rates of continuous and point prevalence abstinence from cannabis, time to relapse, levels of cannabis use, and cannabis related problems at follow up), using the Timeline Followback method Urine Carboxy‐THC: creatinine ratio using Gas Chromatography/Mass Spectrometry INCLUSION CRITERIA: 1. Between 18‐65 years of age (Both males and females) 2. Regular recent cannabis use (average of 5 times per week – self report) 3. Meet DSM‐IV‐TR 'Registered Trademark' criteria for cannabis dependence 4. Has made unsuccessful quit attempts in the past 5. Desire to give up cannabis 6. Prepared to enter a hospital ward for 9 days If NO to any (1 ‐ 6) client is not eligible for SATIVEX trial phone screen, provide usual referral/treatment advice.