Varenicline and nabilone in tobacco and cannabis co‐users: effects on tobacco abstinence, withdrawal and a laboratory model of cannabis relapse. (31st October 2018)

• Record Type: Journal Article
• Authors: Herrmann, Evan S.; Cooper, Ziva D.; Bedi, Gillinder; Ramesh, Divya; Reed, Stephanie Collins; Comer, Sandra D.; Foltin, Richard W.; Haney, Margaret
• Is Part Of: Addiction biology. Volume 24:Number 4(2019)
• Page Start: 765
• Page End: 776
• Publication Date: 2018-10-31
• Subjects: cannabis -- pharmacotherapy -- relapse -- tobacco -- varenicline -- withdrawal; Substance abuse -- Periodicals; Substance abuse -- Physiological aspects -- Periodicals; Substance-Related Disorders -- periodicals; 616.86
• DOI: 10.1111/adb.12664
• Languages: English
• ISSNs: 1355-6215

Abstract

Abstract: Tobacco and cannabis co‐users (T+CUs) have poor cannabis cessation outcomes, but the mechanisms underlying this are not well understood. This laboratory study examined the effects of (1) the partial nicotinic agonist, varenicline, on tobacco cessation among T+CUs, and (2) varenicline, alone, and when combined with the cannabinoid agonist nabilone, on cannabis withdrawal and a laboratory model of cannabis relapse. Non‐treatment‐seeking T+CUs were randomized to active‐varenicline or placebo‐varenicline, and completed a 15‐day outpatient phase; varenicline was titrated to 1 mg BID during days 1–8, and participants were instructed to abstain from tobacco during days 9–15. Participants then moved inpatient for 16 days, where they continued their outpatient medication and tobacco abstinence. Inpatient testing included two, 8‐day medication periods, where active‐nabilone and placebo‐nabilone were administered in counterbalanced order, and measures of acute cannabis effects (days 1–2), withdrawal (days 4–5) and 'relapse' (days 6–8) were collected. Participants in the active‐varenicline group were more likely to achieve cotinine‐verified tobacco abstinence during the outpatient period versus placebo‐varenicline group (46 percent versus 24 percent, respectively), and also reported less mood disturbance and cigarette craving while inpatient. Active‐nabilone attenuated cannabis withdrawal in both groups but did not affect cannabis relapse. Regression analyses revealed that two tobacco‐related variables, i.e. age of first cigarette use, and cigarette craving while inpatient, were independent predictors of cannabis relapse outcomes. Thus, varenicline holds promise in this population, as a tool to examine the effects of tobacco abstinence on cannabis use outcomes, and as a component of smoking cessation treatments targeting T+CUs. Abstract : Tobacco and cannabis co‐users (T+CUs) have poor cannabis cessation outcomes, but the mechanisms underlying this are understudied. This double‐blind, placebo‐controlled study demonstrated that varenicline promotes outpatient tobacco cessation in T+CUs, and that behavioral markers of tobacco use severity predict inpatient cannabis relapse in this population. These relations were robust, independent of cannabis use severity, and not altered by attenuation of cannabis withdrawal via the cannabinoid agonist, nabilone.