Background: In 2013, the Washington State Department of Labor and Industries published guidelines for prescribing opioids to injured workers. We examine trends in opioid prescribing before and after implementation of this guideline.

Objectives: To examine changes in opioid prescribing between 2010 and 2018 and to examine changes in opioid prescribing after implementation of the 2013 guideline.

Methods: Using workers’ compensation pharmacy billing data for workers at least 18 years old, we examined opioid prescriptions from January 2010 through December 2018 to determine the following: percentage of workers with at least one opioid prescription in the first week after injury, percentage with opioids during the acute (first 6 weeks after injury) and the subacute (6-12 weeks after injury) phases, and percentage with more than 7 days’ supply during the acute and subacute phases.

Results: Opioid prescribing in injured workers decreased between 2010 and 2018. The percentage of workers with at least one opioid prescription in the first week after injury decreased from 16.4% in 2010 to 5.9% in 2018. There was a decrease each year in the percentage of workers with opioids dispensed in the acute and the subacute time periods and in the percentage of workers with more than 7 days’ supply in each time period. There was a substantial decrease in the level of opioid prescribing in the subacute period after implementation of the 2013 guidelines.

Conclusions: Implementation of opioid prescribing guidelines was associated with substantial declines in opioid prescriptions in injured workers 6-12 weeks after injury.