RESUMEN
The United States is currently in the midst of the worst drug epidemic in its history, with nearly 64,000 overdose deaths in 2016. In response, pharmaceutical companies have begun introducing abuse-deterrent painkillers, pills with properties that make the drug more difficult to misuse. The first such painkiller, a reformulated version of OxyContin, was released in 2010. Previous research has found no net effect on opioid mortality, with users substituting from OxyContin toward heroin. This paper explores health effects of the reformulation beyond mortality. In particular, I show that heroin is substantially more likely to be injected than OxyContin, increasing exposure to blood-borne diseases. Exploiting variation across states in OxyContin misuse prior to the reformulation, I find relative increases in the spread of hepatitis B and C in states most likely to be affected by the reformulation. In aggregate, the estimates suggest that absent the reformulation, we would have observed approximately 76% fewer cases of hepatitis C and 53% fewer cases of hepatitis B from 2011 to 2015. I find some suggestive evidence that the reformulation also lead to increases in HIV and hepatitis A, although these findings are less robust. These findings have important implications for future policies addressing the opioid crisis.