Trends in Illinois Cannabis Use Incidence and Prevalence

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  • Summary of Research
  • Highlights
  • 5 Contiguous States: Cannabis History


Cannabis consumption pre- and post-legalization of recreational cannabis

Population / Location:

Systematic review of 32 US studies on post-legalization consumption with emphasis on the findings of 11 studies deemed to be of higher methodological quality


Mixed findings with higher quality studies suggesting increases in prevalence of past-month use more often among young adults compared to adolescents; several studies found young women and adolescent binge-drinkers were more likely to increase cannabis consumption post-legalization.


Lachance A, Belanger RE, Riva M, Ross NA. A systematic review and narrative synthesis of the evolution of adolescent and young adult cannabis consumption before and after legalization. The Journal of Adolescent Health. 2022;70(6):848-63


Past year initiation of cannabis use remains highest for 12-17 year olds, followed by 18-25 year olds. Incidence of cannabis initiation remains very low for person 26 or older.


Initiation of cannabis use in the past year for persons 12 or older, has remained largely stable by race/ethnic group, with the exception of Hispanic/Latinos, where there has been increased initiation between 2018 and 2020.


Past year cannabis use is highest for 18-25 year olds and increased between 2018-2019 and 2019-2020. Any past year Cannabis use for 12-17 years and 26 and older remains much lower than 18-25 year olds, with 26 and older experiencing a slight increase from 2019-2020.


With the exception of persons in the "other or poly-racial/ethnic" category, the prevalence of any past-year cannabis use has increased among all racial/ethnic groups in the past two years particularly for White non-Hispanic persons. Black/African American Non-Hispanics have the highest prevalence rate over time.


Illinois and Michigan, the two states that have legalized cannabis, both had 3% increases in any past year use between 2018 and 2020 among residents 12 years of age or older. Other mid-west states showed no increase over the same time while there was only a 1% increase across all US states.


Frequent cannabis use is highest among 18-25 year olds and substantially lower for 12-17 year olds and 26 and older, of whom had the largest increase in between 2017-2020.


Frequent cannabis use remains highest and has been increasing most among Black-non-Hispanics and to a somewhat lessor extent among White-Non- Hispanics.


The largest increase in perceived availability of cannabis as being easy or very easy to obtain was among those 26 years or age or older.


Perceptions that using cannabis 1-2 times per week represents no or only a slight risk increased between 2015 and 2017 among Illinois youth 12 to 17 years old, corresponding to an increase in frequent cannabis use (20+ days per month). Both perceived risk and frequent use have remained constant since then, including in 2019-2020.

Approved Adult-Use Recreational & Medical Cannabis Programs:


In 2008, Michigan legalized medical cannabis for qualifying medical patients. Cannabis dispensaries in the state remained illegal, but permissions allowed patients to cultivate their own plants. In 2016, Michigan expanded their medical program to include licensing and regulation of medical marijuana businesses – allowing for dispensaries within the state. The first licenses were awarded in July 2018. In November 2018, Michigan legalized recreational cannabis use for adults.

Approved Medical Cannabis Program:


In 2014, Missouri permitted only low-THC CBD for seizure disorder patients. In late 2018, Missouri legalized medical cannabis for qualifying patients. The first licenses were awarded in January 2020. There have been no changes to permissions of recreational cannabis use.

Approved CBD/Low-THC:


In 2017, Indiana permitted only low THC oil for seizure disorder patients. In 2018, Indiana amended permissions to


In 2014, Iowa permitted only the use of low-THC CBD products for certain medical patients. In 2018, Kentucky amended permissions to allow use of low-THC CBD for any person. There have been no changes to permissions of medical or recreational cannabis use.


In 2017, Wisconsin permitted low-THC CBD for seizure disorder patients. In 2017, Wisconsin expanded permissions to any medical patient. There have been no changes to permissions of medical or recreational cannabis use.

  • Past Year Cannabis Use Initiation
  • Any Past-Year Cannabis Use
  • Any Past-Month Cannabis Use
  • Any Past-Year Frequent Cannabis Use
  • Perceived Cannabis as Easy to Obtain by Age Group (2012-2020)
  • Correspondance Between Frequent Cannabis Use