Public Release: 

Concurrent tobacco and marijuana use may hamper cigarette smoking cessation

NIH/National Institute on Drug Abuse

Tobacco smokers who also smoke marijuana may be less likely to quit smoking tobacco and less likely to try to quit than those who do not smoke marijuana, according to a study by researchers at The Johns Hopkins University. Dr. Daniel Ford and colleagues interviewed 431 adults who had reported being current tobacco smokers in a study conducted 13 years earlier. In the baseline interview, more than 40 percent of the participants reported having smoked marijuana, with more than 25 percent reporting using it within the previous 30 days (recent use) and nine percent reported daily use for two weeks or more. At the 13-year follow-up, 79 percent of participants who had reported smoking tobacco at baseline were still smoking it.

Recent and daily use of marijuana at baseline were more predictive of continued tobacco smoking than use of marijuana more than a month prior to baseline. Participants who reported recent use were about twice as likely to continue to smoke tobacco 13 years later compared those who did not use marijuana within the preceding 30 days. Those who reported daily marijuana use were over three times more likely to still smoke tobacco. About 66 percent of recent marijuana users reported trying to quit tobacco during the following 13 years compared to 80 percent of those who had never used marijuana.

WHAT IT MEANS: These findings suggest that marijuana use may interfere with tobacco cessation attempts. However, there is no evidence that marijuana use can substitute for tobacco use.


This study, funded by the National Institute on Drug Abuse, was published in the August 2002 issue of Drug and Alcohol Dependence.

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