Assessment of Racial/Ethnic and Income Disparities in Opioid and Other Controlled Medication Prescriptions in California

Kyle Walburg, Pharm.D., Broadway Family Medicine

Background: Nonwhite communities in the United States have been disproportionately affected by most drug epidemics; however, the ongoing opioid epidemic predominantly affects low-income white communities. Potential rationales for why this particular community is most affected have not been explored.

Objective: This study evaluated exposure to prescribed opioids as related to race/ethnicity and income in order to determine if these factors could explain the disproportionate effect on low-income white communities. The study also compared trends in prescriptions for opioids compared with stimulants and benzodiazepines.

Study Design: A population-based study design was used. California’s prescription drug monitoring program was used to evaluate 29.7 million unique records of patients who received a controlled substance prescription from 2011-2015. The mean age of included patients was 46.5 years and patients were 57% female. Specifically, included data was characterized by zip code tabulation areas (ZCTAs) and the racial/ethnic composition and per capita income of the ZCTA. The 29.7 million records corresponded with 1760 ZCTAs in California. The main measure of the study was evaluating what percentage of individuals received at least one prescription each year of an opioid, benzodiazepine, or stimulant (prescription prevalence rate). Medications used to treat opioid dependence such as methadone or buprenorphine were not included in opioid counts.

Results: This study found a nearly 300% difference in prescription prevalence across race/ethnicity and income gradients. In the lowest-income and highest proportion-white population, 44% of adults received at least one opioid prescription each year, compared to only 16% of adults with the highest-income and lowest proportion-white population. Of all individuals aged 15 years or older, 24% received at least one opioid prescription each year. Stimulant prescriptions were most highly concentrated in mostly white high-income areas. Benzodiazepine prescription prevalence was not associated with an income gradient, but was concentrated in mostly white areas (16% of adults with the highest proportion-white population versus 7% of adults in the lowest proportion-white populations). 

Conclusions: The study found that controlled medications were much more likely to be prescribed to those living in majority-white areas. The race/ethnicity and income pattern of opioid overdoses closely matches the prescription rates in these communities, which could imply that these prescription rates have helped lead to majority-white areas being disproportionately affected by the opioid epidemic. Lower quantities of opioid prescriptions in nonwhite communities may have helped protect these communities from the opioid epidemic; however, this lower quantity of prescriptions likely also demonstrates healthcare disparities and a lack of access to care for nonwhite populations. The main limitation of the study is that only prescriptions from California were analyzed. As California has a low rate of controlled substance prescriptions compared to other states, this could limit generalizability. However, California has a highly diverse population and due to its immensity, likely represents a significant share of total prescribing in the United States.

Key Point: Patients in majority-white communities may be disproportionately affected by the opioid epidemic; in contrast, there is likely insufficiently medicated pain in nonwhite communities, based on implicit bias and inequity. Pharmacists can play a critical role in ensuring treatment of pain regardless of race/ethnicity or socioeconomic status.


  1. Friedman J, Kim D, Schneberk T, et al. Assessment of racial/ethnic and income disparities in the prescription of opioids and other controlled medications in California. JAMA Intern Med. 2019; 179(4): 469-476. doi:10.1001/jamainternmed.2018.6721