Study Suggests Medical Marijuana May Increase Misuse of Prescription Drugs

Many studies have cited the benefits of medical marijuana and some have even indicated its potential use in combatting the opioid crisis. However, findings from recently-published research suggest that medical cannabis use may be associated with a higher risk of abusing prescription medication, including pain relievers.

The study, published in the Journal of Addiction Medicine, includes more than 57,000 responses to the 2015 National Survey on Drug Use and Health, in which participants were asked about medical and non-medical use of prescription drugs. Participants were also asked about marijuana use and whether it was recommended by a health care professional. Overall, the survey identified 776 people who used medical marijuana — approximately 1.4% of all respondents.

According to the survey, those who used medical marijuana were more than twice as likely to report non-medical use of prescription drugs, including pain relievers, stimulants, and tranquilizers. Additionally, in an analysis limited to people who used prescription drugs, higher levels of non-medical prescription drug use were prevalent among those who used medical marijuana.

However, other studies have contradicted the notion that marijuana is linked to increased prescription drug use. Previous research has indicated that states in which medical marijuana is legal have lower rates of medical and non-medical prescription drug abuse and related harms, such as opioid overdoses.

In an accompanying commentary, Marcus A. Bachhuber, MD, MSPH, and colleagues at Montefiore Medical Center/Albert Einstein College of Medicine, argued that the findings do not show an increased use of prescription drugs and that other factors may have contributed to the association observed.

According to Dr Bachhuber, even though prescription drug use remained high in the group of medical cannabis users, it is still possible for cannabis use to reduce prescription drug use. He also noted that chronic pain is the most common reason for medical marijuana use.

Study author Theodore L. Caputi, BS, of University College Cork’s School of Public Health, indicated that studies often lack large-scale follow-up data on whether patients are using marijuana together with, or in place of, prescription medication.

“Physicians and practitioners should know that, from cross-sectional data, medical marijuana use is positively associated with non-medical prescription drug use,” he said in a press release about the study.

Although the study’s findings do not prove causal connection between marijuana and opioid use, Dr Caputi concluded that medical marijuana users should be a target population in efforts to combat nonmedical prescription drug use.

In the commentary, the authors concluded, “To fully understand the effect of medical cannabis on the use of other drugs, prospective longitudinal studies randomizing patients to cannabis versus other treatments are urgently needed.”

References

Caputi TL, Humphreys K. Medical marijuana users are more likely to use prescription drugs medically and nonmedically. Journal of Addiction Medicine. 2018. Doi: 10.1097/ADM.0000000000000405