What you need to know about xylazine misuse

The spread of xylazine, also known as tranq, found in street drugs has caused increases in overdose-related deaths. Learn about its overdose risks & effects.

Ophelia team
Xylazine misuse warning
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Arthur Robin Williams, MD

While fentanyl use spreads across the country, and related overdoses increase at alarming rates each year, doctors and drug use researchers have also noticed a correlated—but delayed—increase in the presence of xylazine in illicit drugs. This horse tranquilizer, nicknamed “tranq,” poses a danger to those using opioids and other drugs, and its spread could contribute to further overdose deaths. 

What is xylazine?


Xylazine was originally developed as a horse tranquilizer and has been widely used by veterinarians for decades. It’s still used as a veterinary treatment and can be found under the brand names Sedazine® and Rompum®, among others. Unlike heroin and fentanyl—the drugs it’s most commonly mixed with—xylazine isn’t an opioid. Since it’s a tranquilizer, it depresses bodily functions and can render a person unconscious at high enough doses.

And now xylazine has been introduced to drug markets through veterinary channels and unauthorized, underground manufacturing.

Origins in recreational drug use

In the United States, tranq has been used recreationally or in combination with other recreational drugs since the mid-2000s, but it wasn’t widely used for years. It was first identified in an overdose report in Philadelphia in 2006 and is believed to have been introduced through Puerto Rican drug markets, where it has been in use for longer.

In 2015, xylazine was found in only 0.36% of overdose reports in the 10 areas that were collecting data on it. By 2020, that number had increased to nearly 7%, and in some places, it was substantially higher. According to drug researchers, xylazine seems to be following a similar pattern of dispersal to fentanyl, but it is lagging by about a decade.

How is xylazine used?


Xylazine is rarely used on its own as a recreational drug. Instead, it is most often found cut into or used alongside other drugs—usually fentanyl because it can enhance the opioid’s effects. In fact, over 98% of overdose deaths involving xylazine were in combination with fentanyl.

But fentanyl isn’t the only drug commonly associated with tranq. Over 45% of those overdose-related deaths involved cocaine, and over 23% involved heroin. Alcohol and benzodiazepines are also commonly used in conjunction with the horse tranquilizer.

Pairing with fentanyl

Fentanyl is one of the strongest opioids available, and its recreational use has skyrocketed since its introduction to U.S. drug markets. However, despite being stronger than heroin, fentanyl’s effects are not as long-lasting. In order to experience its euphoric effects, an opioid user must take fentanyl up to five times a day, while heroin is more commonly used only two or three times daily. This causes a number of problems for those using the drug, but xylazine can help counteract some of them.

Xylazine enhances and elongates the effects of fentanyl, increasing its psychoactive properties while reducing the need to use it as frequently. Mixing xylazine with fentanyl allows users to decrease the number of times they’ll need to take opiates each day to quell cravings. While this may seem positive at first glance, xylazine has many negative effects that substantially outweigh this benefit.

What are the risks?

Mixing xylazine with other drugs does not inhibit any of its tranquilizing effects. When it’s mixed with an opioid, the user is less likely to stay conscious during the euphoric period, making them less able to attend to basic needs. Prolonged unconsciousness also makes them more vulnerable to danger. While unconscious, the risks of violence, sexual assault, robbery, and even being hit by a car increase significantly.

The tranquilizing effects of xylazine also make a fentanyl overdose much more likely. Opioid overdoses are the result of extreme depression in respiratory function, leading to unconsciousness and, ultimately, suffocation. The tranquilizer has its own depressing effects, which, when combined with an opioid, are much more likely to prove lethal. Naloxone, the drug used to reverse an opioid overdose, may not have any effect on xylazine, which operates on different mechanisms in the brain. This means it’s harder to bring someone back from an opioid overdose if there’s also tranq in their system.

There are also reports of xylazine leaving users prone to severe skin conditions, such as rashes, abscesses, and necrosis. These conditions make room for infection and disease to take hold and spread more easily. 

Where is it found?

According to drug researcher Jacob Friedman, xylazine seems to be spreading in the same areas that fentanyl originally spread, but not as quickly. Right now, xylazine is most common in Philadelphia, where it is present in over 25% of fentanyl-related overdose deaths. It is also spreading along the East Coast, especially Connecticut and Maryland. It has also been found spreading to the Midwest, with an increasing presence in Illinois. 

How to reduce the danger

For the foreseeable future, finding ways to decrease the danger of xylazine use will be just as important as working to stop its spread. Experts in drug use and harm reduction are pushing for more funding for on-the-spot drug testing locations as well as safe use sites. If those using recreational drugs are able to test their drugs and learn the composition of the substances, they are better able to make informed decisions. This will lead to fewer accidental overdoses caused by the presence of unknown substances in a drug. 

Safe use sites also offer opioid users access to clean needles and safe facilities where they can receive medical attention if they need it. This can help decrease the number of deadly overdoses in the short term while also helping stop the spread of disease.

Opioid users with reliable access to medical care may also want to seek out medication-assisted treatment (MAT), which can be used to manage cravings and prevent overdoses, giving individuals the opportunity to then address the social and psychological sources of addiction.


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