Tobacco Smokers Were 19 Times More Likely to Relapse to Marijuana in a Lab Setting | Research

The takeaway

Across five laboratory studies, cigarette smokers were 19 times more likely to relapse to marijuana than non-smokers, and this was not explained by tobacco's direct pharmacological effects on marijuana relapse.

Read this if you use both tobacco and marijuana and are considering quitting either or both.

Cigarette smokers had 19x higher odds of marijuana relapse

What the researchers found

Study 1 combined data from five inpatient laboratory studies (51 daily marijuana smokers averaging 10 joints/day). When active marijuana became available, 49% relapsed on day one. Cigarette smokers (75%) were dramatically more likely to relapse than non-cigarette smokers, with an odds ratio of 19.

Study 2 isolated tobacco's direct effects by testing 15 marijuana-and-tobacco dual users under two conditions: smoking tobacco as usual versus after 5+ days of tobacco cessation. High relapse rates occurred regardless of tobacco condition (>87%). Tobacco cessation did not directly affect marijuana relapse, suggesting that being a tobacco smoker is a marker of relapse vulnerability rather than tobacco directly driving marijuana relapse.

Why it matters

This finding has major clinical implications. Marijuana treatment programs should assess tobacco smoking status as a key predictor of relapse. The 19-fold increased odds of relapse represent one of the strongest predictors identified in marijuana treatment research.

The numbers in context

51 participants in Study 1. 49% relapsed on day 1. Cigarette smokers: 75% relapse. Non-smokers: much lower (OR=19 for smokers). Study 2: 15 dual users. >87% relapsed regardless of tobacco condition.

How the study worked

Study 1: Combined analysis of 5 inpatient studies. 51 daily marijuana smokers (10 joints/day). Day 1: active marijuana. Days 2-4: no marijuana (withdrawal). Days 5-8: active marijuana available (relapse). Study 2: Within-subjects comparison in 15 dual users: smoking as usual vs. tobacco-quit condition.

What this study cannot tell us

Laboratory relapse model may not perfectly reflect real-world relapse. Non-treatment-seeking participants differ from treatment seekers. Study 2 was small (15 participants). The high base rate of relapse (49% day 1) reflects the laboratory setting. The odds ratio of 19 may be inflated by the small non-smoker comparison group.

How to read the evidence

Combined laboratory studies with within-subjects confirmation; moderate evidence for a robust clinical marker.

When this study was published

Published in 2013. The relationship between tobacco and cannabis co-use continues to be studied.

The bigger picture

This study suggests that tobacco and marijuana co-use reflects a shared vulnerability rather than a direct pharmacological interaction. People who smoke both substances may have higher levels of impulsivity, reward sensitivity, or other traits that make abstinence from either substance more difficult.

Questions still open

Should marijuana treatment programs integrate tobacco cessation? What characteristics of tobacco smokers explain their higher marijuana relapse risk? Would addressing shared vulnerability factors improve outcomes for both substances?

Common questions

Why are tobacco smokers more likely to relapse to marijuana?

This study tested whether tobacco directly causes marijuana relapse by comparing dual users who were smoking tobacco versus those who had quit tobacco for 5+ days. Relapse rates were equally high (>87%) in both conditions, suggesting tobacco does not directly drive marijuana relapse. Instead, being a tobacco smoker appears to be a marker of an underlying vulnerability to relapse.

Should I quit tobacco and marijuana at the same time?

This study does not directly answer this question, but the finding that tobacco smoking status is the strongest predictor of marijuana relapse suggests these substances are linked. Some treatment approaches advocate addressing both simultaneously, while others prioritize one at a time. The key finding here is that tobacco use status should be assessed in any marijuana treatment plan.

Read the original research

Predictors of marijuana relapse in the human laboratory: robust impact of tobacco cigarette smoking status.

Biological psychiatry, 73(3), 242-8

View on PubMed ↗Publisher’s paper ↗

Citation

Haney, Margaret; Bedi, Gillinder; Cooper, Ziva D; Glass, Andrew; Vosburg, Suzanne K; Comer, Sandra D; Foltin, Richard W. (2013). Predictors of marijuana relapse in the human laboratory: robust impact of tobacco cigarette smoking status.. Biological psychiatry, 73(3), 242-8. https://doi.org/10.1016/j.biopsych.2012.07.028