By Ginika Igboke 

A bipartisan coalition of 41 state and territorial attorneys general is calling on Congress to pass legislation aimed at curbing the growing abuse of xylazine, a veterinary tranquilizer increasingly found mixed with illicit drugs such as fentanyl.

Arkansas Attorney General Tim Griffin announced on April 1 that the group sent a letter dated March 31 to congressional leadership, urging swift passage of the Combating Illicit Xylazine Act. The legislation—introduced in February 2025 in both the Senate (S.545) and the House (H.R.1266)—has already garnered support from more than 100 bipartisan co-sponsors.

If enacted, the bill would classify xylazine—commonly referred to as “tranq” or the “zombie drug”—as a Schedule III controlled substance under the Controlled Substances Act, giving federal authorities expanded tools to regulate and track its distribution.

Rising Threat From Drug Adulteration

Officials warn that xylazine’s growing presence in the illicit drug supply is worsening the already deadly opioid crisis. The substance is not approved for human use but is increasingly being used as an additive in fentanyl and heroin, significantly increasing the risk of fatal overdoses.

“In recent years, the United States has seen a rise in xylazine being used to cut fentanyl and heroin and distributed as a recreational drug,” Griffin said. “The addition of xylazine, which is a high-powered, Narcan-resistant tranquilizer, to the already deadly fentanyl is increasing the number of fatal overdoses.”

Because xylazine does not respond to naloxone (Narcan), the standard treatment for opioid overdoses, it presents unique challenges for first responders and public health officials.

Griffin emphasized that the proposed legislation is carefully designed to avoid interfering with legitimate uses of xylazine by veterinarians, farmers, and ranchers.

International Supply Chains and Enforcement Efforts

Authorities say the drug is often trafficked into the United States through international supply chains. According to Griffin, federal officials have identified Mexican cartels as key distributors, often pairing xylazine with fentanyl sourced from China.

Recent enforcement actions underscore the scale of the issue. In April 2025, customs officials at a Chicago air cargo facility seized 18 pounds of xylazine shipped from China and destined for addresses in Cleveland and Philadelphia.

Later that year, in September 2025, four China-based companies were indicted on trafficking-related charges for allegedly facilitating the flow of illicit substances, including xylazine. One of the companies, Guangzhou Tengyue Chemical, was also sanctioned by the U.S. Treasury Department.

In another case from November 2024, a chemical company based in Wuhan, along with several of its employees, was indicted in Los Angeles for allegedly selling fentanyl precursor chemicals and xylazine to U.S. buyers.

State and Federal Coordination

The attorneys general noted that many states have already taken steps to regulate xylazine under their own controlled substances laws, though classifications vary. They argue that a unified federal approach is necessary to effectively combat the drug’s spread.

“We agree that Congress must act quickly to classify the illicit use of xylazine under Schedule III of the federal Controlled Substances Act,” the coalition wrote. “The Combating Illicit Xylazine Act provides critical tools that will enable the Drug Enforcement Administration to track its manufacturing, prevent diversion, and require reporting on its illicit use.”

The letter was co-led by Griffin, Connecticut Attorney General William Tong, New York Attorney General Letitia James, and Tennessee Attorney General Jonathan Skrmetti, and signed by attorneys general from dozens of states and U.S. territories.

Legislative Momentum Builds in Congress

The legislation has already made progress on Capitol Hill. On March 26, the Senate Judiciary Committee advanced the bill in a 19–3 vote. The measure is led in the Senate by Sens. Chuck Grassley (R-Iowa) and Catherine Cortez Masto (D-Nev.), while Reps. Jimmy Panetta (D-Calif.) and August Pfluger (R-Texas) are spearheading the House version.

Lawmakers from both parties have emphasized the urgency of addressing the growing threat posed by xylazine.

“It’s being mixed with opioids, driving deadly overdoses, and making this crisis even harder to fight,” said Connecticut Attorney General William Tong. “Congress must act now to give law enforcement the tools to stop its spread and save lives.”

Supporters say the bill represents a targeted response to a rapidly evolving drug crisis—one that aims to curb illicit use while preserving the substance’s essential role in veterinary medicine and agriculture.