A sharp increase in heroin overdoses in the Cincinnati area — more than 200 in the last two weeks, killing three — has medical and law enforcement officials on edge. One possible culprit for the uptick? A super strong synthetic animal tranquilizer called carfentanil.

You might have heard of fentanyl, which is used as a quick-acting painkiller. Fentanyl can be 50 times stronger than heroin, and carfentanil is as much as 100 times more potent than fentanyl, The New York Times reports. An amount the size of a snowflake is enough to kill someone.

Officials say carfentanil has no practical uses for humans — it’s suited more for livestock and elephants — but nevertheless, it’s been popping up in batches of heroin linked to recent overdoses.

It’s so strong that police officers are carrying overdose-reversing nalaxone sprays for themselves, just in case they get a whiff of the stuff or come in contact with the smallest flake of it. Officers have stopped testing drugs in the field.

“We’d never seen it before,” Dr. Lakshmi Kode Sammarco, the coronerin Hamilton County told the NYT. “I’m really worried about this.”

The carfentanil is likely being made in China or Mexico and then heading up to Ohio in heroin shipments. Along with Cincinnati, it’s shown up in Columbus, OH, the Gulf Coast of Florida and central Kentucky.

Recently, officials have been responding to 20 or 30 calls a day regarding overdoses, and sometimes have to give people two, three, or five doses of nalaxone spray to revive them, instead of just one spray.

“Our antidote, our Narcan, is ineffective,” Sheriff Jim Neil of Hamilton County said, referring to a brand name for nalaxone. “It was meant for heroin. It wasn’t meant for fentanyl or carfentanil.”

Drug Linked to Ohio Overdoses Can Kill in Doses Smaller than a Snowflake [The New York Times]

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