Increasing trends in Schedule II opioid use and doctor shopping during 1999-2007 in California.

PURPOSE: To examine the age and gender-specific trends of Schedule II opioid use among California residents, with special reference to multiple provider users (doctor shoppers).
METHODS: Utilizing data from the California Prescription Drug Monitoring Program, we examined age and gender-specific trends of Schedule II opioid use during calendar years 1999-2007. Specifically, we analyzed the following: (1) the prevalence of Schedule II opioid users among California's population and (2) the proportion of these opioid users who were doctor shoppers (defined as an individual who used more than five different prescribers for all Schedule II opioids he or she obtained in a calendar year).
RESULTS: Among all age and gender groups, the prevalence of Schedule II opioid users in California increased by 150%-280% and the prevalence of doctor shoppers among users increased by 111%-213% over 9 years. The prevalence of opioid users was lowest among 18-44 year old men (1.25%) and highest among 65-year and older women (5.31%) by 2007. The prevalence of doctor shoppers was approximately 1.4% among those up to age 64 years and 0.5% among those 65 years and older. The gender difference in doctor shoppers among all age groups was negligible. On average, the cumulative morphine-equivalent amount of Schedule II opioid per individual obtained per year was threefold to sixfold higher for doctor shoppers than for the general population across different age and gender groups.
CONCLUSIONS: Age and gender differences in opioid use were relatively small, whereas the trends for use of opioids and multiple providers grew at a disquieting rate.