WASHINGTON, April 21, 2023—An approved animal sedative is being mixed with fentanyl to create a deadly drug mixture known as “Tranq.”

The U.S. Drug Enforcement Administration is warning the American public of a sharp increase in the use of the sedative xylazine with fentanyl.

The sedative has also been mixed with heroin and other illicit drugs, according to the U.S. Food and Drug Administration.

Xylazine is a non-opioid agent the FDA originally approved in 1972 as a sedative and analgesic for use in veterinary medicine.

There are no approved uses of xylazine for humans.

“Xylazine is making the deadliest drug threat our country has ever faced, fentanyl, even deadlier,” said DEA Administrator Anne Milgram. “DEA has seized xylazine and fentanyl mixtures in 48 of 50 states. The DEA Laboratory System is reporting that in 2022 approximately 23 percent of fentanyl powder and 7 percent of fentanyl pills seized by the DEA contained xylazine.”

Xylazine and fentanyl drug mixtures place users at a higher risk of suffering a fatal drug poisoning.

Because xylazine is a sedative, not an opioid, it is not treatable with Narcan. However, Narcan should be administered for opioid overdoses and consider xylazine exposure if patients are not responding to Narcan or when there are signs or symptoms of xylazine exposure, according to the FDA.

People who inject drug mixtures containing xylazine also can develop severe wounds, including necrosis—the rotting of human tissue—that may lead to amputation.

According to the Center for Disease Control and Prevention, 107,735 Americans died between August 2021 and August 2022 from drug poisonings, with 66 percent of those deaths involving synthetic opioids like fentanyl.

As of January, Philadelphia’s Health Department found that 90 percent of illicit drugs sampled tested positive for xylazine. Tranq was first seen in Puerto Rico.

The Mexican Sinaloa and Jalisco cartels, using chemicals largely sourced from China, are primarily responsible for the vast majority of the fentanyl being trafficked in communities across the United States, according to the DEA.

Other names associated with the deadly mixture include “tranq dope,” “sleep-cut,” “Philly dope” and “zombie drug.”