When the first abuse-deterrent formulation of the opioid OxyContin was introduced in 2010 as a way to deter misuse of the drug, it may have set off an increase in hepatitis C infections by pushing users toward injectable heroin, a new study suggests.
Acute hepatitis C infections in the United States were declining in the 1990s and plateaued around 2003. But beginning in 2010, rates have been rising.
Researchers with RAND Corporation told Medscape Medical News that while hepatitis C infection rates rose nationwide after abuse-deterrent OxyContin was introduced, states with higher rates of OxyContin misuse prior to the reformulation of the drug saw hepatitis C infection rates increase three times faster than other states.
The original version of OxyContin can be crushed or dissolved and injected for a greater high. Abuse-deterrent versions of opioids prevent the drugs from being crushed or dissolved. Previous studies have shown that abuse-deterrent opioids drove abusers to switch to injectable heroin, which in turn led to a sharp increase in heroin overdoses after 2010.
Because injectable drug use is a major risk factor for hepatitis C, researchers set out to determine whether the opioid epidemic may have contributed to the increase in new hepatitis C infections. For the study, researchers studied hepatitis C infection rates in each state from 2004 to 2015, and examined levels of OxyContin misuse before the reformulation of OxyContin occurred.
Researchers found that states with the highest rates of OxyContin misuse before 2010 saw a 222 percent increase in hepatitis C infections following the reformulation of the drug. States with lower levels of OxyContin misuse had a 75 percent increase in hepatitis C infections after 2010. Researchers also noted that prior to 2010 there was very little difference in hepatitis C infection rates between the two groups of states.
“It is important that strategies that limit the supply of abusable prescription opioids are paired with policies to ease the harms associated with switching to illicit drugs, such as improved access to drug treatment and increased efforts to identify and treat diseases associated with injection drug use,” said Rosalie Liccardo Pacula, the study’s co-author, co-director of the RAND Opioid Policy Tools and Information Center and the RAND Drug Policy Research Center.