Carfentanil reemerges in Michigan opioid overdoses, health department says

(FOX 2) - Michigan health officials are sounding an alarm as a dangerous opioid reemerges in the state, leading to 11 reported overdose deaths.

Carfentanil, a synthetic opioid that was developed for veterinarian use in large animals, is 100 times more powerful than fentanyl.

Big picture view:

The return of a powerful opioid not approved for humans has the Michigan health department warning residents about its reemergence in the unregulated drug supply, contributing to overdoses, and threatening the state's progress in tackling the drug epidemic.

Carfentanil is associated with 11 overdose deaths between January and June 2025, according to MDHHS.

A hundred times more potent than fentanyl - one of the main culprits behind America's surge in drug-related deaths over the past decade - it was identified in deaths in both mid-Michigan and Southeast Michigan counties.

"Carfentanil is an extremely potent and deadly drug," said Michigan Chief Medical Executive Natasha Bagdasarian. "We’re urging people who use unregulated drugs – and their loved ones – to carry naloxone, an easy to administer nasal spray that can reverse opioid overdoses and save lives.

The backstory:

Carfentanil was first reported in fatal overdoses in Michigan in 2016 when it contributed to 107 deaths. In 2017, it killed 111 people. 

Since then, overdoses tied to the synthetic painkiller had fallen to zero by 2021 and 2022. However, it jumped back up in 2023 with health officials identifying it in 14 overdose deaths.

Michigan has seen improvements in its overdose numbers since the U.S. reached the height of the opioid epidemic when thousands of people were succumbing to addiction.

According to MDHHS data, Michigan saw a gradual increase in opioid deaths from 2000 before fentanyl arrived, pushing the rate even higher. The Michigan Overdose Data to Action Dashboard estimates the epidemic peaked in 2021 when more than 3,000 people died.

What is carfentanil?

Carfentanil is much more potent than the substances that spiked the opioid epidemic. Its higher strength - which is intended to affect large animals - can kill those even with a tolerance for opioids.

It rapidly depresses the nervous system, which can cause death. 

To reverse the impacts of carfentanil, multiple doses of naloxone are needed to avoid a fatal overdose.

State of Play:

Carfentanil is frequently a contributing factor in overdose deaths and is often used with cocaine, methamphetamine, and other stimulants, MDHHS says.

Those ingesting those substances may not be aware they contain carfentanil. 

That's why MDHHS is encouraging everyone to carry naloxone, which they can get through their local health department or police department.