A sedative approved for animals is increasingly being found in illegal drugs, which could lead to overdoses, health officials said in an April 2 alert.

Medetomidine, the veterinary sedative, has been detected in a growing number of areas through drug seizures by law enforcement officers, samples of drug products and paraphernalia, and wastewater testing, the Centers for Disease Control and Prevention and the White House Office of National Drug Control Policy said in the health alert network notice.

The sedative addition to illegal drugs is putting “people at risk for overdose,” the notice stated. Medetomidine, also known as rhino tranq, mede, and dex, can cause serious problems, such as an abnormally slow heartbeat. Withdrawal symptoms include anxiety and vomiting.

Medetomidine was first identified in illegal drugs in 2021. It appeared in major cities such as Chicago in recent years and, by August 2024, had been detected in samples and specimens from at least 18 states and the District of Columbia.

Reports of medetomidine in drugs soared from 247 in 2023 to 8,233 in 2025. Most reports came from the northeast. Wastewater testing from October 2025 through January 2026 also found medetomidine in wastewater in 14 states.

Medetomidine is approved as a sedative for dogs, while its dextro-isomer, dexmedetomidine, can be used legally for sedating humans.

The testing of illegal drugs has identified a lack of preservatives commonly found in the approved formulations. That means that rather than utilizing pharmaceutical products, people are likely creating medetomidine in “clandestine laboratories” before adding it to the drugs, primarily fentanyl, officials said.

“Because fentanyl is involved in most overdoses involving medetomidine, opioid overdose reversal medications (OORM; e.g., naloxone) should be administered to restore normal breathing in suspected overdoses,” they said.

Naloxone or similar medications can be repeated every two to three minutes as personnel work to make sure the patient takes at least one breath every five seconds.

People at risk of an overdose should carry naloxone or an alternative and have a plan to use it, or have someone nearby use it, if an overdose happens, according to the alert.

Health care workers are also being instructed to keep an eye out for signs of medetomidine-related intoxication and withdrawal.

Signs of intoxication include heart rates as low as 32 beats a minute, profound sedation, and low blood pressure. Signs of withdrawal include severe high blood pressure, tremors, and chest pain.

People going through withdrawal regularly require care in emergency rooms or intensive care units, officials said.

The withdrawal symptoms can begin within hours of the last use of medetomidine and usually peak 18 to 36 hours later.

​Frank Tarentino, associate chief of operations for the Drug Enforcement Administration (DEA) Northeast Region, told The Epoch Times in February that the DEA’s nine labs across the country have seen a sharp increase in medetomidine.

Tarentino said medetomidine is produced in China and India and is “100 percent supplied by and enabled by the cartels” as a way to increase profit.

​“The synthetics that are killing Americans are coming from these two countries, predominantly, as well as the precursor chemicals,” he said.

The No. 1 exporter of medetomidine is China, and the No. 1 importer is the United States, he added.

​In early 2016, fentanyl became a major threat to the United States.

High-level meetings involving Beijing and Washington prompted China to make fentanyl illegal to produce and distribute inside the country in 2019, Tarentino said.

Soon after, the precursor fentanyl chemicals began showing up in Mexico, where they were then synthesized into fentanyl and trafficked into the United States, he said.

​Likewise, other synthetic drugs such as nitazenes, synthetic opioids, and drugs such as medetomidine started being produced illicitly and smuggled out of China into the United States.

​“I mean, there’s no doubt that this is being weaponized in a way to, number one, make money,” Tarentino said.

Darlene McCormick Sanchez contributed to this report.