A recent study reveals that xylazine, a tranquilizer commonly used in veterinary medicine, is present in nearly one-third of fatal opioid overdoses in Philadelphia.
Since 2014, U.S. life expectancy has steadily declined. Major factors include obesity, liver disease, suicide, and above all, opioid overdoses—synthetic drugs with effects similar to morphine. The United States has more than twenty million addicts.
The most prevalent opioids are heroin and fentanyl, often mixed with other substances like synthetic cannabinoids or, more recently, xylazine—a sedative routinely used in horse care since the late 1960s.
Xylazine is not an opioid itself but acts as a cutting agent. Research on its health impacts when combined with opioids remains limited, though evidence indicates the mixture may increase overdose death risk.
Published in the journal Injury Prevention and based on post-mortem analyses, a recent study shows xylazine is now involved in nearly a third of fatal opioid overdoses in Philadelphia. It was detected in only 2% of cases from 2010 to 2015, rising to 31% in 2019.
The opioid epidemic in the United States "continues to evolve," the authors conclude. They caution that national overdose death counts involving xylazine may be underestimated, as not all toxicology labs routinely test for it.
Xylazine is FDA-approved for animal use only, and in humans, it can trigger severe, potentially life-threatening side effects.
Sourcing street xylazine is hard to trace, but it requires only a veterinary prescription—readily obtainable for horse owners or through informal channels.
Reasons for mixing xylazine with opioids are unclear due to sparse research. However, focus groups in Philadelphia report that users perceive it as helping to prolong opioid effects. Further studies are essential to clarify these synergistic risks.
