A new and increasingly dangerous drug combination is raising alarm among law enforcement and public health officials across the country. The U.S. Drug Enforcement Administration (DEA) has reported a surge in the presence of medetomidine, a powerful veterinary sedative, being mixed with fentanyl, making an already deadly opioid crisis even more perilous.

Medetomidine, like xylazine, is not approved for human use and is intended solely for veterinary purposes. However, it is significantly more potent than xylazine and presents even greater challenges for overdose reversal.

“Fentanyl is extremely deadly but at least Narcan, if it’s used early enough, may prevent a few deaths,” District 27 District Attorney Jack Thorp said. “When mixed with xylazine, the chances of death increase dramatically and death is even more likely when fentanyl is mixed with medetomidine.”

The DEA says this new combination has been found in various forms, including fake prescription pills, gel capsules, powder mixtures and drug paraphernalia. The increasing presence of medetomidine has made it harder for first responders to save lives, as it significantly reduces the effectiveness of naloxone (Narcan), the primary medication used to reverse opioid overdoses.

Data from the U.S. Centers for Disease Control and Prevention (CDC) underscores the growing threat.

In Philadelphia, Penn., medetomidine was detected in 72% of illegal opioids tested during the last four months of 2024, replacing xylazine as the most common adulterant. Survivors of overdoses involving this combination are often hospitalized with a severe and life-threatening withdrawal syndrome, which current treatments are ill-equipped to address.

“People need to be aware that these substances are present in our communities and are making a very lethal drug even more dangerous,” Thorp warned. “We will continue working with law enforcement to combat the spread of these deadly drugs and to hold accountable the people involved in their distribution.”

Authorities are urging the public to remain vigilant, seek help for substance use disorders and report suspicious activity as they confront this alarming new chapter in the opioid crisis.