Study Discovers Using Cannabis Does Not Lower Long-Term Heroin Use

Published on: 

A recent study investigated if there was a connection between cannabis use and if it would lower heroin use.

Cannabis has been called at times the “gateway drug” (1). A recently published study discovered that long-term heroin use does not decrease cannabis use (2). The idea of cannabis assisting in the opioid epidemic was supported by experts but the findings in this new study may suggest otherwise (2).

"Cannabis is becoming increasingly recognized as a therapeutic product," says study author Dr. Jack Wilson, a researcher at The Matilda Centre for Research in Mental Health and Substance Use at the University of Sydney (2). Wilson added (2), “Despite suggestions that cannabis may be used as a method for reducing opioid use, we found no evidence to suggest a relationship between the use of these [substances].”

Opioid dependency has been a growing issue in the US and continues to become a bigger problem. In 2021, the Centers for Disease Control and Prevention (CDC) announced that over 80,000 deaths occurred that year. States have been struggling to deal with the effects of the epidemic and are working on resolutions to help with the fight. For example, the states of New York and Illinois worked on updating their medical cannabis legislation and have accepted the cannabis plant to be used as an alternative treatment method to prescription opioids (2).


Cannabis legislation has been changing throughout the country with the hope that the plant could be a tool in decreasing opioid use and other drugs (2). “Increasing the availability of cannabis is unlikely to have an impact one way or the other on the opioid crisis and overdose death rate,” Dr. Andrew Saxon commented, a professor of psychiatry and behavioral sciences at the University of Washington School of Medicine (Seattle, Washington), and is also a member of the American Psychiatric Association's council on addiction psychiatry (2).

Detailed in the study, researchers reviewed data on more than 600 patients who use heroin (2). The list of participants comprised of individuals who were or weren’t in treatment for the drug. Use of other drugs such as, prescription opioids were investigated in the study (2). Prior studies covered short-term data but regarding this recent study, researchers reviewed data over a 20-year time period (2).

Research from the study showed that cannabis use was a common trait among heroin users. One matter to note from the research was that there was no link regarding patterns of use between the two drugs or that cannabis decreased the use of opioids long-term (2).

"Much more research needs to be done," Dr. Stephanie Widmer, a medical toxicologist and emergency medicine physician who practices in New York, explained (2).


  1. Is Marijuana A Gateway Drug? (accessed Nov 29, 2023).
  2. Jhaveri, K. Cannabis Use Does Not Reduce Long-Term Heroin Use, Study Finds (accessed Nov 29, 2023).