Send to

Choose Destination
J Am Med Dir Assoc. 2018 Jan;19(1):59-64.e1. doi: 10.1016/j.jamda.2017.07.017. Epub 2017 Sep 9.

Effects of Legal Access to Cannabis on Scheduled II-V Drug Prescriptions.

Author information

Department of Economics, University of New Mexico, Albuquerque, NM.
Department of Psychology, University of New Mexico, Albuquerque, NM. Electronic address:
Department of Emergency Medicine, University of New Mexico, Albuquerque, NM; Industrial Rehabilitation Clinics, Albuquerque, NM.
Industrial Rehabilitation Clinics, Albuquerque, NM.



Co-prescribing of scheduled drugs is endemic in the United Sates, increasing health risks to patients and the burden on healthcare systems.


We conducted a pragmatic historical cohort study to measure the effect of enrollment in a state-authorized United States' Medical Cannabis Program (MCP) on scheduled II-V drug prescription patterns.


Eighty-three chronic pain patients, who enrolled in the New Mexico MCP between April 1, 2010 and October 3, 2015, were compared with 42 nonenrolled patients over a 24-month period (starting 6 months before enrollment for the MCP patients) using the Prescription Monitoring Program. The outcome variables include baseline levels and pre- and postenrollment monthly trends in the number of drug prescriptions, distinct drug classes, dates prescription drugs were filled, and prescribing providers.


Twenty-eight MCP patients (34%) and 1 comparison group patient (2%) ceased the use of all scheduled prescription medications by the last 6 months of the observation period. Age- and sex-adjusted regressions show that, although no statistically significant differences existed in pre-enrollment levels and trends, the postenrollment trend among MCP patients is statistically significantly negative for all 4 measures (decreases in counts of -0.02 to -0.04, P values between <.001 and .017), whereas the postenrollment trend is 0 among the comparison group. Controlling for time-invariant patient characteristics suggested that MCP patients showed statistically significantly lower levels across all 4 measures by 10 months postenrollment.


Legal access to cannabis may reduce the use of multiple classes of dangerous prescription medications in certain patient populations.


Marijuana; Prescription Monitoring Program; cannabis; opioids; scheduled medications; substitution

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center