FILE: A Hazardous Materials technician removes his mask after leaving the scene of an overdose that killed two people in Lawrence, MA on Jul. 17, 2017. Authorities alerted the specialized team because they suspected the presence of carfentanil in the
A chemical relative of fentanyl so toxic it was once developed as a weapon is resurging in the U.S.
Carfentanil, which is 100 times more powerful than fentanyl and 10,000 times stronger than morphine, has made a dramatic return to America’s drug supply, federal officials say. Carfentanil is so potent, a microscopic dose smaller than a grain of salt can be fatal.
What is carfentanil?
The backstory:
Carfentanil is a synthetic opioid in the same family as fentanyl. It first permeated the U.S. drug scene a decade ago, but it saw a major dip after China banned it following hundreds of overdose deaths.
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For years, carfentanil was studied as a chemical weapon. Russian forces used it on Chechen separatists in 2002.
What they’re saying:
“It’s like a biological weapon,” said Michael King Jr., founder of the Opioid Awareness Foundation. “If the world thinks we had a problem with fentanyl, that’s minute compared to what we’re going to be dealing with with carfentanil.”
“You’re talking about not even a grain of salt that could be potentially lethal,” Frank Tarentino, the DEA’s chief of operations for its northeast region, told The Associated Press. “This presents an extremely frightening proposition for substance abuse dependent people who seek opioids on the street today.”
Experts say even multiple high doses of overdose-reversing naloxone might not be enough when carfentanil is involved.
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Why is it resurging?
Big picture view:
According to the U.S. Drug Enforcement Administration, the return of carfentanil could be linked to China’s crackdown on some ingredients used to make fentanyl. Mexican traffickers may be using it to fortify fentanyl that’s been weakened by China’s crackdown, or they may be trying to make it themselves.
By the numbers:
In 2025, carfentanil was identified 1,400 times in U.S. DEA drug seizures, compared with 145 in 2023 and only 54 in 2022, according to DEA records viewed by The Associated Press.
In 2024, overdose deaths involving carfentanil nearly tripled compared to the previous year, with 413 deaths across 42 states and Washington, D.C., according to CDC data reviewed by the AP.
The DEA has been involved in several major carfentanil seizures in recent months. In October, the DEA Los Angeles Field Division found 628,000 pills containing carfentanil, and in September, officials seized more than 50,000 counterfeit M30 pills from a person at a gas station in Washington state that tested positive for carfentanil.
The Source: This report includes information from The Associated Press.