Carfentanil, an elephant tranquilizer that experts say is 10,000 times stronger than morphine and 100 times stronger than fentanyl, is wreaking havoc in the US. The dangerous drug, sometimes sold as fentanyl, has left first responders scrambling to save lives. And while its use had previously been confined to the Midwest (particularly Ohio, where the opioid epidemic has left almost no family untouched) a recent overdose in Maine has left New England officials on high alert for overdoses on the drug.

While some carfentanil users may know the power of the drug they’re getting, most often, the drug is added to heroin and other opiates without the user’s knowledge. The drug is known best for its fatalities. Carfentanil itself is so toxic that simple skin contact can cause a medical emergency. Even for experienced and long-term opioid users, the drug is quickly deadly.

On October 15, emergency workers in York, Maine rushed to revive a 24-year-old man who had overdosed on carfentanil. It took five doses of the anti-narcotic medication, Narcan, to revive him. In Ohio, at least 8 deaths were attributed to the tranquilizer last month. And an investigation in Michigan recently discovered that 18 opiate-related deaths dating back to July can be traced to carfentanil. The deaths, ruled accidental overdoses, were heroin users who likely had no idea the drug was tainted. In fact, most of the toxicology reports showed the decedents in Michigan had other opiates active in their system upon death. Officials in that state said that one of the first clues to carfentanil use was that Narcan had little to no effect on the overdose victims. In response to the influx of the drug, some states are encouraging first responders to stock a larger supply of naloxone. It works, but it takes a large amount to revive patients.

So where is the drug coming from? Apparently, it originates from China. An Associated Press investigation revealed that Chinese vendors offer to sell the dangerous elephant tranquilizer openly online, with no questions asked. While China already has already made laws to prohibit export of fentanyl and 18 related compounds, there is little enforcement, and many vendors simply lie on their paperwork to avoid scrutiny. Waiting for China to crack down on rogue pharmaceutical companies could take many years. In the meantime, first responders will be on the front lines fighting to save lives from this powerful drug as well as other opiates.