Mapping Pharmacy Deserts

Dima Qato spent more than a decade working as a community pharmacist and public health advocate in Chicago’s underserved refugee and immigrant communities before joining the Mann School in fall 2020.

Through her experiences and public health training, Qato—the daughter of a pharmacist—views pharmacy access as a human rights issue and a frequently overlooked piece of the healthcare access puzzle.

“The World Health Organization has considered geographic access to pharmacies one of the key determinants of access to essential medicines for decades,” says Qato, a senior fellow at the USC Schaeffer Center for Health Policy & Economics and the Hygeia Centennial Chair at the Mann School. “Despite the important role of pharmacies in providing essential medicines to the community, 15 years ago, when I started my PhD, no one really considered pharmacy access—not even people investigating health equity and disparities in medication adherence. It wasn’t part of the conversation.”

Today, an estimated 100 million Americans lack convenient access to a pharmacy. To call attention to the issue, Qato coined the term “pharmacy desert.”

Pharmacy Access Initiative

Her latest project is an interactive, nationwide mapping tool showing the location of every pharmacy in the United States and which neighborhoods fall into the category of pharmacy deserts, or pharmacy shortage areas—as well as those at risk of falling into that category. The Pharmacy Access Initiative is a collaboration of the Mann School, the Schaeffer Center, the Spatial Sciences Institute at the USC Dornsife College of Letters, Arts and Sciences, and the National Community Pharmacists Association, which represents independent pharmacies across the country.

The mapping tool identifies nearly 1 in 4 neighborhoods—representing millions of Americans—as pharmacy shortage areas. A shortage area is defined as one where the distance to a pharmacy is greater than 10 miles in a rural area, 2 miles in a suburban area, 1 mile for urban areas and a half-mile in neighborhoods that are low income and have low vehicle ownership.

Prior research by Qato found that one-third of neighborhoods in the largest U.S. cities—including Los Angeles—are pharmacy deserts. The most affected neighborhoods are segregated Black or Latino communities within these cities.

Fostering Health Equity

Qato hopes the mapping tool will inform federal and state policy changes that improve health equity.

For example, Medicare Part D and Medicaid health plans have pharmacy networks that often exclude independent (and some chain) pharmacies that largely serve Black and Latino populations. Qato says such policies are a form of structural racism that forces historically marginalized populations to travel farther to their nearest pharmacy to fill their medications. Excluding pharmacies from networks also leads to the underutilization—and, often, closure—of pharmacies located in these neighborhoods, she notes.

“It’s also important to ensure that local pharmacies are actually stocking essential medicines and offering essential services they are authorized to provide,” Qato says.

The map could also provide a framework to promote accountability—including in the regulation of pharmacy benefit managers, who play an important role in low and inequitable pharmacy reimbursement and pharmacy closures.

The mapping tool will be rolled out via training webinars for stakeholders in the coming months.