Heavy cannabis use (20 or more days of use within the past 30 days) is associated with several adverse health outcomes, including cannabis use disorder and cannabis hyperemesis syndrome. Cannabis use disorder is characterized by dependency and difficulty controlling use. Cannabis hyperemesis syndrome includes symptoms such as recurrent nausea and vomiting. Smoking cannabis on a regular basis has also been linked to chronic bronchitis, wheezing, exercise-induced shortness of breath, chest tightness, cough, and mucus production. For more information about cannabis-related health effects, please visit the Health Effects web page.
Adults who use cannabis should follow safety measures such as storing and disposing of cannabis products where they cannot be accessed by children and pets, not driving while under the influence of cannabis, or using cannabis with alcohol.
In California, approximately one in three people aged 21 years or older who used cannabis in 2023 reported heavy cannabis use.
Adult cannabis use data was obtained from the 2017-2023 California Health Interview Survey (CHIS), an annual phone and web-based survey of a random sample of approximately 20,000 California adults. The data are considered representative of the age 18 and older population of California.
Heavy cannabis use is defined as “use of marijuana, hashish, or another THC product” 20 or more days within in the past 30 days.
Adults are defined as individuals aged 21 years and older.
For questions, please contact us at cannabis@cdph.ca.gov.