Xylazine: The New Krokodil? The Dangerous Rise of a Flesh-Eating Drug

Doctor and nurse putting bandage on a patient

There have been warnings and alerts for a few years about xylazine, a veterinary sedative that has been found mixed into illicit drugs. But these warnings have not come close to expressing the horror experienced by many people unfortunate enough to encounter this drug in their usual drug supplies. In fact, the drug is beginning to elicit comparisons to another horrific drug: krokodil.

Krokodil was a home-cooked drug derived from over-the-counter medications sold in Russia that contained codeine. It was highly addictive as well as physically, emotionally and spiritually damaging. Krokodil addicts were in such terrible condition that they did little but steal to support their habits and then cook up the drug. Gradually, the effects of krokodil made themselves known. Users developed huge, gaping wounds that revealed tendons and bones. Recovery from addiction to this drug—if it could even be accomplished—was grueling.

The same damage is being seen now in areas where xylazine is being added to products on the illicit drug market. Xylazine has the ability to destroy large areas of the user’s flesh. The drug shuts off circulation to areas where injections have been done and even to other areas of the body where there were no injections. Soft tissues die, creating large, oozing open wounds. Extensive medical treatment is needed to get the wound to heal. Amputation may be required if the wound won’t heal.

Xylazine is a Popular Veterinary Sedative

This drug has been used for years in veterinary medicine where it is known by the brand name Rompum. It is used on horses, dogs, cats, sheep and other animals as a sedative, pain reliever and muscle relaxant. It has no approved uses for humans. But drug dealers are now adding this veterinary sedative to many substances sold on the illicit market, such as heroin, cocaine, methamphetamine and fentanyl.

On the illicit market, the drug is nicknamed “tranq.”

Xylazine Has Been Found Across the Country

Powder laboratory

Pennsylvania and the Northwest have been the hardest hit by this drug’s toxic effects, followed by California. The epicenter of harm has been in Philadelphia. In 2023, sources in the city announced that 90% of drug samples seized in the city contained xylazine.

In nearby Rhode Island, 40% of drug samples have been tainted with the drug. Some areas of Massachusetts, including western Massachusetts, are seeing xylazine in 50% to 75% of samples.

Across the country, xylazine has been found in 48 states. According to the Drug Enforcement Administration, the presence of xylazine in drug supplies increases the risk of overdose with every use.

Effects of Xylazine

Xylazine slows the central nervous system, slowing breathing and reducing heart rate, movement and blood pressure.

Other common effects include:

  • Dry mouth
  • Drowsiness
  • Low blood pressure
  • Abnormally increased heart rate followed by abnormally slow heart rate
  • Low blood sugar
  • Lowered body temperature
  • Respiratory depression
  • Catatonic immobilization
  • Coma

Because of their partly or fully immobilized states, the media has started referring to xylazine users as “zombies.”

The immobilization that results from xylazine use can be so severe that the drug user lies motionless for many hours. Their muscle fibers can begin to break down from the hours of compression. This results in a toxic and potentially disabling or fatal condition called rhabdomyolysis.

In northern climates, it’s also easy to die from exposure to cold weather if you can’t move.

In the real world, images from Philadelphia show the tragic effects of this drug. Drug users on the street stagger in a semi-conscious state, get hung up in a crouching position or simply lie in a lifeless form on the sidewalk.

drug dealing on a street

Why is Xylazine in U.S. Drug Supplies?

The presence of xylazine seems to prolong the effects of opioids like heroin or fentanyl. Per weight, it is also much cheaper than fentanyl. It has some of the same physical and mental effects as opioids so this may make the opioid products seem more potent. Therefore drug dealers are adding this cheap xylazine to the heroin or fentanyl they sell.

However, because the effects of xylazine include central nervous system depression, the drug can also intensify the life-threatening effects of opioids. Breathing can become even slower until the user is at risk of death. In some cases, if the user had only consumed heroin or fentanyl, they might survive, but the addition of xylazine tips them over into a fatal overdose.

Drug Combinations Become More Common and More Dangerous

The situation with street drugs is so out of control right now that it is common to find fentanyl in cocaine and methamphetamine supplies as well as heroin supplies or counterfeit pills. Apparently, some drug dealers add fentanyl to their cocaine or methamphetamine supplies so that their customers more quickly become dependent on them.

That’s because coke and meth may only be used recreationally at parties or on weekends. But if a customer develops a craving for fentanyl, they are far more likely to want the drug every day. So adding fentanyl to a stimulant like cocaine or meth is a fast way to create a customer who has a more urgent need for the drug dealer.

Therefore, any illicit drug purchase may contain fentanyl, heroin, xylazine or any combination of the three drugs. Test kits to determine if a sample contains xylazine only became available in early 2023. There is no antidote for xylazine like there is for opioid drugs.

It’s the same situation with any pills purchased on the illicit market. Any drug dealer can buy a pill press, coloring agent and binder and make pills out of heroin, fentanyl and/or xylazine.

Xylazine Facts

How it’s used: It can be swallowed or injected. If it is added to a powdered drug, it may be snorted.


Loss of life: The estimated number of drug-poisoning deaths in the United States involving xylazine grew from 260 in 2018 to 3,480 in 2021, an increase of 1238%, with the highest numbers of such deaths during that period reported in Pennsylvania, Maryland, New York, and Connecticut.

Vermont also struggles with xylazine deaths. Between 2021 and the first ten months of 2022, overdose deaths involving xylazine rose from 29 to 54.

Arrival on the drug market: Xylazine was first spotted in Puerto Rico in 2001. It was intermittently found in American drug supplies between 2006 and 2018. By 2023, it had been found in states across the continent.

Recovering from Exposure to Xylazine

This is a relatively new drug on the U.S. market and so drug rehabs may have to adapt to the special needs of those exposed to the drug. For example, some people starting their recoveries may still suffer from large wounds. Severe high blood pressure may occur as a person comes off this drug. A medically supervised withdrawal may be needed to protect the patient’s health.

The dangers of drug addiction continue to develop in unexpected and life-threatening ways. Drug abuse is not safe anywhere, at any time. The arrival of xylazine in America’s drug supplies is just another example of this. The right thing to do is to encourage any loved one trapped in addiction to get the help they need to recover now before any more harm can occur.


  • LA Care. “LAC DPH Health Advisory: Xylazine in Illicit Drugs Increasing Overdose Risks.” LA Care, 2023. LA Care.
  • California: National Public Radio. “An animal tranquilizer is making street drugs even more dangerous.” NPR, 2022. NPR.
  • Fox News. “Fentanyl is even deadlier when mixed with xylazine (or ‘tranq’).” Fox News, 2023. Fox News.
  • The White House. “NEJM Publishes ONDCP Op-ed on the Medical and Public Health Imperatives Surrounding Xylazine.” The White House, 2023. The White House.
  • Stateline. “States, Cities Scramble to Combat Animal ‘Tranq’ in Street Drugs.” Stateline, 2023. Stateline.


Karen Hadley

For more than a decade, Karen has been researching and writing about drug trafficking, drug abuse, addiction and recovery. She has also studied and written about policy issues related to drug treatment.