Marijuana laced with fentanyl, the zombie drug xylazine, and nitazenes were listed as the top concerns people will face in the evolving drug ecosystem, during a Thursday hearing before the House Energy and Commerce Subcommittee on Health.

The emergence of fentanyl marked the third wave of the opioid epidemic following the abuse of prescription painkillers and a rise in heroin use that prompted major concern during former President Barack Obama’s administration. Fentanyl is a legitimate pharmaceutical drug that is used to treat severe pain and advanced-stage cancer patients.

Fentanyl-laced marijuana and hemp

Oakland County, Michigan, Sheriff Michael Bouchard, vice president of government affairs for the Major County Sheriffs Association, said the legalization of marijuana in certain states has led to an “adulteration” of marijuana products.

“We’ve actually found outside of our supply chain, the legal supply chain of marijuana, illegal marijuana has been tampered with and has fentanyl in it, and so we’ve seen all of these things really need a regulated, inspected process,” Bouchard said.

Dr. Timothy Westlake, an emergency medicine physician at ProHealth Care Oconomowoc Memorial Hospital in Wisconsin, said he has recently seen overdoses in his emergency room of people who had ingested fentanyl-laced marijuana.

Rep. Morgan Griffith (R-VA) said the southwest region of his state had also dealt with major problems with THC gummy bears, or candy-like chews that are supposed to contain CBD but may have an “unregulated, unknown amount of THC” packed inside.

“Kids get a hold of them and they think they’re candy, and then they overdose,” Griffith said. “And then, when I say overdose, I’m not talking about deaths at this point, but there have been some indications there may actually have been some brain damage.”

Westlake said he saw marijuana poisonings last week from gummies.

“I’ve seen it in the past … two or three episodes last week alone,” Westlake said.

Xylazine

Fentanyl is also increasingly mixed with a drug called xylazine. Also known on the street as “tranq,” it puts users in a zombielike state of consciousness.

The Food and Drug Administration has only approved xylazine as a sedative for large animals, such as horses and deer. As a medicine that veterinarians use, it is not a controlled substance, which has made it easier to acquire in the U.S.

Xylazine is often combined by cartel chemists with fentanyl in order to “amplify sedation and euphoria,” at the cost of causing respiratory suppression and a high lethal risk to the user, according to Westlake.

A user who takes xylazine and fentanyl, either by injecting, snorting, swallowing, or inhaling it, can experience unique physical symptoms not seen among users of other types of drugs, prompting the “zombie” name.

Xylazine causes blood vessels to constrict, limiting blood flow. Without adequate blood supply, the skin takes on the appearance of lesions at the injection site and throughout the body. The skin stretches out and disintegrates, posing a risk of limb amputation.

Naloxone, also referred to as Narcan, is an antidote for opioid overdoses, but because xylazine is not an opioid, the emergency medicine only stops the effects of fentanyl, not the tranquilizer, making those who overdose more likely to have lethal repercussions.

Tranq is already here. In 2024, the Drug Enforcement Administration found xylazine mixed with fentanyl in 49 of 50 states.

Nitazenes

Nitazenes are a type of manmade or synthetic opioids that can be as potent and deadly as fentanyl.

Westlake testified that nitazenes have been implicated in hundreds of deaths nationwide recently, “emerging as the newest spigot.”

The DEA put out a notice to its Washington division in 2022 warning that nitazenes were being found in drugs on the street in the District of Columbia, but it has taken several years for the drug to expand to other regions.

“First identified around 2019 in the Midwest, this dangerous drug has moved into the Southern states and, more recently, along the Eastern seaboard,” the DEA notice reads. “Much more potent than heroin and morphine (similar to fentanyl), [the substance] is being mixed into and marketed as other drugs to make drugs more potent and cheaper to produce. The major concern: This drug can and has caused deadly overdoses in unsuspecting victims.”