5.21.1 Estimates of other drug and tobacco co-use among young people
As noted in Section 5.5, tobacco use in adolescence is associated with other risky behaviours, including use of other drugs. Australian and international research consistently shows that people who smoke are more likely to drink alcohol (including frequent binge drinking),1 use cannabis and other illicit drugs2-4 and use inhalants.5
While many student surveys estimate tobacco use as well as other drug use, not many consistently report data on the co-use of these substances.
Among Australian secondary school children in 2017 aged 12–17 years who reported concurrent substance use (tobacco and another substance) in the previous 12 months, 42% had taken ecstasy, 39% cannabis, 36% amphetamines, 38% hallucinogens, and 13% had used tranquilisers, as well as tobacco at the same time.6 Other Australian research8 has found that young people engaged with alcohol and other drug (AOD) services in 2013 and 2017 had higher rates of tobacco use compared with community samples. Moreover, among the young people engaged with AOD services, tobacco use prevalence did not decrease over time in line with declines in this age group in the wider population.8
International surveys have also provided estimates of young people’s tobacco and other drug co-use. In England, a 2023 student survey found 1% of pupils aged 11-15 years had recently smoked, drunk alcohol and taken drugs, while 2% had done any two of these behaviours.9 In a study from the US, nationally representative data from Wave 7 (2022/2023) of the Population Assessment of Tobacco and Health (PATH) Study showed that the prevalence of exclusive tobacco use was similar to that of tobacco and cannabis co-use among young people aged 12-24 (9.3% vs. 9.4%).10
5.21.2 The relationship between drug use and tobacco uptake
Patterns of drug use among young people, including tobacco use, appear to have changed over time. Repeated national school surveys in Finland11 showed that, between 2003 and 2019, alcohol use and smoking decreased among adolescents aged 15 to 16, while experimentation with cannabis increased. The association between smoking and cannabis experimentation also weakened over this period, and experimentation increased among both those who smoke and those who do not smoke between 2015 and 2019. The authors suggest that cannabis experimentation, once concentrated among young people who smoke, is now extending to those who do not.
For users of multiple substances, the order of first substance used has changed over time. Australian research has shown that of those who use multiple substances, tobacco is no longer the first substance used. A study examining the uptake of alcohol, cannabis and cigarettes among young people aged 18-21 using data from six waves of the National Drug Strategy Household Survey from 2001 to 2016 found that among those who used multiple substances, cigarette use had declined over time as the first product used. Of the respondents who had used multiple substances in 2016, 55% reported using alcohol before cigarettes (compared to 36% in 2001), and 41% used cigarettes before cannabis (compared to 62% in 2001).12
The role of alcohol in the uptake of smoking
Research among Australian secondary school children in 2017 aged 12–17 years found that among those who had consumed alcohol in the past week, 33% listed having ‘tried smoking’ as a negative outcome of their drinking.6 Nationally representative longitudinal research from Ireland published in 202513 found that, after adjusting for risk factors, early ‘age at first alcohol’ and ‘risky adolescent alcohol use’ independently predicted substance use, including tobacco use, by age 20. Of those who reported early alcohol use, 38% went on to use tobacco by age 20. Relative to early alcohol users, older ‘age at first alcohol’ was associated with dose-response reductions in the odds of tobacco use at age 20. Adolescents at age 17 with ‘high-risk’ alcohol use had double the odds of tobacco use at age 20, relative to those with low-risk alcohol use at age 17.13 However, similar longitudinal research from New Zealand published in 2016 found that initial associations between age of first drinking and later nicotine dependence became non-significant after adjusting for risk factors related to characteristics of the individual and family during childhood.14
The role of cannabis in the uptake of smoking
Early Australian longitudinal research published in 2005 using a sample of 1943 participants aged 14-15 from Victoria found that those who regularly used cannabis were more likely to progress to tobacco initiation and dependence, even after controlling for confounding factors such as peer group and family influences.15 A nationally representative US longitudinal study published in 2025 similarly found that cannabis use among young people was associated with progression to regular tobacco use.16
Despite speculation that the relationship between tobacco and cannabis use could be explained by shared risk factors, research does suggest a bidirectional relationship. A 2022 UK study found potential causal pathways between cannabis use and smoking initiation in both directions.17 In a 2024 systematic review and meta-analysis18 of longitudinal studies (mostly from the US) researchers tested the association between cannabis and nicotine (including cigarettes, cigars, hookah, smokeless tobacco and e-cigarettes). Findings showed that nicotine use at baseline was associated with later cannabis initiation, and cannabis use at baseline was associated with later nicotine initiation (in the pooled youth and adult data, but not in the youth only data), supporting a bidirectional relationship between the two.18
5.21.2.1 The effect of other drug use on the level of consumption of tobacco
Concurrent use of tobacco and alcohol appears to increase use of both. For example, in research among US college students from 2011 who both smoked and drank alcohol, (mean age 20 years) students drank more while smoking and smoked three times as many cigarettes, on average, during drinking episodes.19 High rates of drinking, common among young adults, may contribute to the transition from less-than-daily to daily cigarette smoking, for example by making smoking seem more satisfying and enjoyable. Preliminary research among young adults found that alcohol consumption was associated with a reduction in some of the negative effects associated with smoking and with an increase in subsequent smoking levels.20 Early evidence from a US longitudinal study among young adults followed over three years, from 2001-2002, suggested that even occasional smoking was predictive of hazardous drinking and alcohol use disorders, after controlling for baseline drinking behaviours.22 The severity of nicotine dependence was found to significantly predict alcohol-related problems among adolescents who smoked in a 2010 smoking cessation clinical trial.23
5.21.3 Factors that explain the relationship between drug use and tobacco uptake
The relationship between smoking and the use of other drugs is likely to be due to a combination of individual, social, environmental and commercial factors, as well as attitudes towards, and policy related to, tobacco and other drugs.
5.21.3.1 Individual-level influences
There may be a number of individual-level factors associated with tobacco and other drug use. Research has shown that the biological changes in the brain caused by early exposure to nicotine may influence neurological response to drugs such as alcohol and cannabis, as well as other drugs of abuse, potentially leading to a greater risk of ongoing use and addiction.4 Research among Finnish twins published in 2010 suggests that several common genetic influences may be related to tobacco and cannabis (and other illicit drug) use; common and unique environmental factors were also very important, while the direct impact of uptake of tobacco smoking explained most of the variation in the initiation of illicit drug use.24
Evidence from The Netherlands suggests young adolescents who report higher levels of hopelessness and sensation seeking are at higher risk for an early onset of substance and poly-substance use (including alcohol, tobacco and cannabis).25 A 2021 US longitudinal study examining individual level risk factors for poly-substance (alcohol, cannabis, nicotine) use among a sample of 1263 adolescents, 83% of which had ever smoked, found that, at baseline and over time, more depression symptoms, more anxiety symptoms, weaker mood regulation expectancies, and lower grade point average (GPA) were each associated with an increase in poly-substance use.26
A 2014 US twin study27 found that experiencing a strong initial reaction (positive or negative) to smoking was associated with later nicotine dependence and later cannabis problems. However, experiencing a strong first reaction (positive or negative) to cannabis only predicted later cannabis problems, not tobacco problems.27
5.21.3.2 Social influences
Friends’ substance use can have an influence on uptake of tobacco. A longitudinal study from 2017 found that an offer of any substance from a close friend was associated with later tobacco use among adolescents, even when tobacco was not the substance being offered.28
Parents’ use of, and attitudes toward, tobacco and other drugs affects their offspring. Longitudinal research from Europe, published in 2021, found that perceived parental permissiveness towards the use of legal drugs (i.e. smoking and drinking alcohol), predicted adolescents’ use of illicit drugs.29 Adolescents in the study who perceived their parents to hold permissive norms towards smoking and drinking, had double the risk of being illicit drug users at follow-up, compared to the adolescents who perceived their parents to hold restrictive norms.29 Similarly, other longitudinal research has shown that strict parental rules regarding alcohol is associated with a reduction in use of other substances, specifically tobacco and cannabis, as an indirect effect of reduced alcohol use.30 A US study from 2017 found that parental alcohol use disorder was associated with an increased risk for the initiation of multiple substances, including alcohol, cigarette and cannabis use, among offspring.31
5.21.3.3 Environmental influences
For legal drugs such as tobacco and alcohol,32-34 research has, for each substance separately, shown that density of Australian retailers is disproportionately greater in areas of disadvantage and close to schools (for tobacco evidence see Section 11.9.6.1). Moreover, greater density of tobacco retailing is associated with smoking uptake (see Section 11.9.6.2.3) and greater density of alcohol retailers is associated with consumption of alcohol by adolescents.32 However, in Australia there is little published research examining the co-location of tobacco and alcohol outlets near young people and in disadvantaged areas.35 International studies36,37 however, have looked at the combined density of both tobacco and alcohol retailers, and found that the most deprived neighbourhoods had higher densities of both tobacco and alcohol retailers, compared to more affluent areas.
In places, such as Ontario, Canada38 and many states in the US,39-42 where cannabis is legalised, research shows that retail density, and accessibility to cannabis as well as other legal drugs, such as alcohol and tobacco, is higher in places where there are more disadvantaged people, and near young people, compared to the general population. A 2023 study40 from California found that combined retailer density—tobacco/vape and cannabis—was associated with higher past-month adolescent co-use of tobacco and cannabis.
5.21.3.4 Commercial influences
In the US where cigars and cigarillos are often used for smoking ‘blunts’ whereby the user removes some or all of the tobacco and replaces it with cannabis, cigar products are often marketed with references to cannabis on the packaging. Experimental research has looked at this marketing practice to try to understand whether cannabis references on cigar packaging has the potential to influence young people’s understanding of cigar product ingredients, perceptions of addictiveness, harm and appeal, as well as future use susceptibility. The research found that marketing of cannabis on cigar packaging lowered young people’s perceptions that the product contained tobacco or nicotine, and led to increased susceptibility for both substances.43 Research has shown that the incorporation of large graphic health warnings on cigars are effective at discouraging the use of blunts, when compared to smaller text-only warnings.44
See Section 10.19.3 for more on cannabis and a shifting product focus for the tobacco industry.
5.21.3.4.1 Modes of administration that facilitate co-use
Methods of cannabis and tobacco co-use can include the use of spliffs/joints (i.e., mixing tobacco and marijuana into a RYO cigarette), blunts (made from the tobacco leaf casing of little cigars/cigarillos, or blunt wraps, and filling with either a mix of cannabis and tobacco or just cannabis— a method common in the US), putting two products in one’s mouth at the same time, using vape devices with both nicotine and THC, and mixing tobacco and cannabis in a bowl, bong or hookah.53
Mixing tobacco and cannabis is common among co-users, and research has shown it is associated with nicotine dependence.54 In a national sample of Australians aged 14 and above who reported using both tobacco and cannabis (2.5%), 78.4% of co-users reported mixing tobacco and cannabis.7
Unlike in Australia, where the use of cigarillos is low among people who smoke and has declined significantly over time (see Section 1.12.2), little cigars/cigarillos are a tobacco product commonly repurposed for cannabis use in the US—referred to as a ‘blunt’. The casing of little cigars/cigarillos is constructed from tobacco leaves, therefore, regardless of whether the tobacco filling is removed, risks exposure to nicotine.55 A 2023 study55 from the US found ‘blunt’ use to be a point of nicotine initiation and placed young people at risk of progression to all forms of tobacco and nicotine use (cigars, e-cigarettes, cigarettes, hookah).
Researchers suggest that policies designed to regulate nicotine device characteristics that enable interchangeable use of tobacco or cannabis, or co-use, such as vaping devices, may be a good starting point in addressing co-use.56
5.21.4 How tobacco policy affects other drug use
US research from 202657 found that recreational cannabis legalisation is associated with an increase in cannabis-only use as well as co-use of tobacco and cannabis among adults. Another US study found that strong smokefree policies were associated with reduced co-use of cannabis and tobacco, specifically in blunts, relative to states lacking in comprehensive smokefree policies.58
Longitudinal research published in 202459 using data from the European School Survey Project on Alcohol and Other Drugs (ESPAD) argued that, in places where cannabis legislation is being considered, comprehensive tobacco control could help to counter the potential, unintended increases in cannabis use among adolescents. As an average over the more than 40 European countries included, a five percentage point decrease in the prevalence of adolescents who had ever smoked a cigarette (interpreted as a result of tobacco control policy) was accompanied by a 2.5% decrease in national prevalence of adolescent lifetime cannabis use. Some countries, such as Ireland and the Ukraine, saw much more substantial declines in lifetime smoking prevalence, which were accompanied by substantial cumulative declines in the prevalence of lifetime cannabis use.59
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References
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