Varenicline helped tobacco-cannabis co-users quit tobacco, while nabilone eased cannabis withdrawal | Research

The takeaway

In a controlled study, the smoking cessation drug varenicline helped tobacco-cannabis co-users achieve tobacco abstinence (46% vs 24%), while the synthetic cannabinoid nabilone reduced cannabis withdrawal symptoms but didn't prevent relapse.

People who use both tobacco and cannabis, those trying to quit either or both, and clinicians treating co-use.

Varenicline: 46% vs 24% tobacco abstinence; tobacco craving predicted cannabis relapse

What the researchers found

Varenicline doubled cotinine-verified tobacco abstinence (46% vs 24%) and reduced mood disturbance and cigarette craving. Nabilone attenuated cannabis withdrawal in both groups but did not affect cannabis relapse. Age of first cigarette and cigarette craving were independent predictors of cannabis relapse.

Why it matters

Tobacco and cannabis are frequently co-used, and tobacco use worsens cannabis cessation outcomes. This study is among the first to test medications specifically for this co-use pattern, finding that addressing tobacco (varenicline) may be key to improving cannabis outcomes.

The numbers in context

Tobacco abstinence: 46% varenicline vs 24% placebo. Nabilone attenuated cannabis withdrawal but not relapse. Age of first cigarette and cigarette craving predicted cannabis relapse outcomes independently.

How the study worked

Two-phase study: 15-day outpatient phase with randomized active or placebo varenicline plus tobacco abstinence instruction, followed by 16-day inpatient phase with crossover nabilone/placebo and cannabis exposure, withdrawal, and relapse paradigms. Non-treatment-seeking tobacco-cannabis co-users.

What this study cannot tell us

Small sample of non-treatment-seeking participants. Laboratory relapse model may not reflect real-world conditions. Short duration. Nabilone dosing may not have been optimized for relapse prevention.

How to read the evidence

Moderate: randomized design with biological verification, but small sample and non-treatment-seeking participants.

When this study was published

Published in 2019.

The bigger picture

The finding that tobacco-related variables predicted cannabis relapse challenges the common approach of treating cannabis and tobacco use as separate problems. Addressing tobacco dependence may be a necessary component of cannabis cessation treatment for co-users.

Questions still open

Would combining varenicline and nabilone produce better cannabis cessation outcomes than either alone? Should cannabis treatment programs routinely address tobacco use? Does the type of tobacco product (cigarettes vs vaping) affect the co-use relationship?

Common questions

If I use both tobacco and cannabis, which should I quit first?

This study suggests addressing tobacco may help with both. Varenicline improved tobacco abstinence, and tobacco-related factors (age of starting, craving) independently predicted cannabis relapse outcomes.

Can nabilone help with cannabis withdrawal?

Yes, in this study nabilone reduced cannabis withdrawal symptoms. However, it did not prevent cannabis relapse in the laboratory model, suggesting withdrawal relief alone may not be sufficient for long-term abstinence.

Read the original research

Varenicline and nabilone in tobacco and cannabis co-users: effects on tobacco abstinence, withdrawal and a laboratory model of cannabis relapse.

Addiction biology, 24(4), 765-776

View on PubMed ↗Publisher’s paper ↗

Citation

Herrmann, Evan S; Cooper, Ziva D; Bedi, Gillinder; Ramesh, Divya; Reed, Stephanie Collins; Comer, Sandra D; Foltin, Richard W; Haney, Margaret. (2019). Varenicline and nabilone in tobacco and cannabis co-users: effects on tobacco abstinence, withdrawal and a laboratory model of cannabis relapse.. Addiction biology, 24(4), 765-776. https://doi.org/10.1111/adb.12664