Trends in co-prescribed opioids and benzodiazepines, non-prescribed opioids and benzodiazepines, and schedule-I drugs in the United States, 2013 to 2019.

Concurrent opioid and benzodiazepine users are at increased risk of overdose death, compared to opioid-only users. The objective of this study was to understand recent time trends in opioid and benzodiazepine concurrent use, misuse, and schedule-I drug use, and how these differ by age, sex and geographic region. Commercial, United States medical insurance claims data and urine drug test results from 2013 to 2019 were used to study the outcomes of concurrent use (n = 756,258), schedule-I drug use (n = 746,672) and prescription misuse (n = 452,523). Drug use outcomes were studied at quarterly time points for each year. Data analysis included joinpoint regression models to estimate quarterly drug use rates, determined by positive urine tests for corresponding drug categories, and was conducted from November 2021 through January 2022. Concurrent use decreased from 19.3% to 9.8%, misuse generally decreased from 75.6% to 55.1%, and schedule-I use increased from 8.9% to 13.8%, from 2013 to 2019. Concurrent use decreased at greater rates after 2016, after the Centers for Disease Control and Food and Drug Administration guidelines against concurrent use were released, while schedule-I use increased, notably after the 2014 hydrocodone reschedule. This indicates a potential shift from prescription use to non-prescribed drug use, where most affected groups included males, younger individuals, and those residing in Northeastern regions. Study results support public health initiatives focused on policy that increases access to multimodal pain management and substance use disorder management programs-critical steps in preventing patients from seeking non-prescribed drugs for self- medicating due to pain or addiction.