The enactment of laws legalizing marijuana on the state level is associated with a reduction in the use of schedule III opioid drugs among Medicaid enrollees, according to a new study published in the journal Drug and Alcohol Dependence.

Investigators with the University of California, San Diego assessed the relationship between recreational marijuana access laws and opioid utilization among Medicaid enrollees.

Authors reported: “We found no evidence to support the concern that recreational marijuana legalization increased opioid prescriptions received by Medicaid enrollees. Instead, there was some evidence in some model specifications that the legalization might be associated with reduction in Schedule III opioids in states that implemented legalization in 2015.”

By contrast, researchers did not identify an association between adult use access laws and the decreased use of schedule II opioids.

A prior study by the same authors reported that medical cannabis access laws were associated with a significant reduction in schedule III opioid prescriptions among Medicaid enrollees, but that the laws were not associated with any changes in the prescription use of schedule II opiate drugs. Authors speculated that this result may be because physicians are more reticent to recommend medical cannabis options to these patients.

The study’s results are consistent with those of several others finding that legal cannabis access is associated with reduced levels of opioid use, abuse, hospitalization, and mortality.

The full text of the study, titled “Recreational marijuana legalization and prescription opioids received by Medicaid enrollees,” appears in Drug and Alcohol Dependence.