Does Smoking Weed Make It Harder to Quit Vaping?

Secondary analysis of a single-site randomized clinical trial conducted in Massachusetts (June 2022–May 2024). Three arms: varenicline + counseling, placebo + counseling, and enhanced usual care (text-based support). Cannabis use measured via self-reported days per week and CUDIT scores at baseline. Primary outcome was biochemically verified 7-day point prevalence nicotine vaping abstinence at week 12.

Clinicians sometimes worry that treating nicotine addiction in someone who also uses cannabis is futile—that the cannabis will sabotage the quit attempt. This trial provides evidence against that assumption. For the roughly 75% of young vapers who also use cannabis (per RTHC-00156's data), these findings suggest vaping cessation programs shouldn't exclude or deprioritize dual users.

This fits into a growing body of evidence showing that co-occurring substance use doesn't necessarily doom individual cessation efforts. RTHC-00156 found that 31.7% of adolescent dual users achieved abstinence from both vaping and cannabis simultaneously—suggesting that quitting one substance may even support quitting the other. The day-level co-use finding here also aligns with research on cross-substance cue reactivity.

Single-site trial in Massachusetts limits generalizability. Self-reported cannabis use (no biochemical verification). Secondary analysis—the trial wasn't designed or powered to detect cannabis-related effects on vaping cessation. The 12-week follow-up is relatively short for assessing long-term quit maintenance.