What You Should Know About Xylazine

An animal sedative that's dangerous for humans is showing up in street drugs across the country, and it's spreading fast. As a result of the drug, called xylazine, users are left vulnerable and exposed for hours at a time.

Xylazine, also called "tranq" or "tranq dope," has been found in heroin and fentanyl, say public health officials. Increasingly, it's linked to overdose deaths.

In Rhode Island, around 44% of street drug samples contained xylazine, according to an ABC News report by Nicole Wetsman. According to a report released in June, xylazine was found in the medication supply in 36 states and the District of Columbia. New York City health officials claim that while xylazine was found in 25% of medication samples, its true saturation level is much higher. In Philadelphia, xylazine was found in more than 90 percent of dope samples as of 2021.

The drug is often associated with horrific wounds and decaying skin tissue called eschar, which is sometimes called abscesses or lesions. These wounds can become infected and cause amputations.

“The tranq dope literally eats your flesh,” says Brooke Peder, a 38-year-old tattoo artist in Philadelphia who has had a leg amputated due to an infected tranq wound, to the New York Times’ Jan Hoffman. “It’s self-destruction at its finest.”

Even more troubling is that In Philadelphia's emergency department, skin and soft tissue injuries quadrupled between 2019 and 2021.

“The wounds, for lack of a better term, are gnarly,” Jen Shinefeld, a field epidemiologist at the city’s health department, told STAT earlier this year.

Generally, these aren't the same type of wounds that occur when injecting drugs. The wounds sprout far from the injection site; even those who snort or smoke xylazine-contaminated opioids - tranq dope - report developing them. Although they aren't caused by an infection, they can become infected if they aren't treated.

According to the US Food and Drug Administration (FDA), the drug can be difficult to distinguish from opioid use due to its inability to show up on routine toxicology screenings. Naloxone, a standard treatment for opioid overdoses, might not work with xylazine because it's not an opioid.

Xylazine was first developed by Bayer in 1962, according to a November memo from the Drug Enforcement Administration (DEA). The FDA approved xylazine as a veterinarian-prescribed sedative and pain reliever ten years later. The DEA notes that veterinarians use it to “calm and facilitate handling, perform diagnostic and surgical procedures, relieve pain or act as a local anesthetic” for cattle, sheep, horses, dogs, cats, deer, rats, and elk.

Researchers investigated xylazine in humans for the same purposes but ended their trials because it depressed the central nervous system and caused low blood pressure. It is not known if yohimbine hydrochloride and tolazoline hydrochloride are safe or effective in humans to reverse xylazine's effects.

The origin of xylazine is unclear, but it was likely used in Puerto Rico in the 2000s. Drug enforcement officials have not been monitoring xylazine for abuse because it has not been listed as a controlled substance for humans or animals. According to the Times, neither hospitals nor state medical examiners typically test for it.

Public health officials are still trying to get a handle on the drug, as well as how best to respond to it. Researchers have not widely studied xylazine’s effects on humans, and they don’t know why it’s causing such gruesome wounds. Amid rising fentanyl overdoses, public health experts are also trying to figure out how best to treat overdoses in which xylazine may have played a role, reports STAT News’ Andrew Joseph.

Frequently Asked Questions About Xylazine

1. What is xylazine?

The non-opioid medication Xylazine is used as a muscle relaxant and sedative in veterinary medicine. Despite not being approved for human use, xylazine is increasingly found in street drugs, often combined with fentanyl (a powerful synthetic opioid).

2. Is xylazine FDA-approved for human use?

No.

Since 1962, the FDA has approved its use only for veterinary use due to its harmful side effects.

3. How long has xylazine been available illicitly?

According to reports, xylazine first appeared on illicit drug markets in Puerto Rico in the early 2000s under the name "Anestesia de Caballo." Since 2006, xylazine has been included in toxicology reports for the Philadelphia Medical Examiner's Office.

4. What is the reason for the use of xylazine along with fentanyl?

In comparison to heroin and other opioids, fentanyl's "high" lasts for a very short time. Xylazine may be added, at least in part, to mimic the heroin high and extend fentanyl's effects. It is important to note that not everybody who uses fentanyl intentionally seeks out xylazine. It is possible that people are not aware that drugs they are buying and using contain xylazine.

5. How long does xylazine last in humans?

There have been reports of humans overdosing on xylazine that have lasted between 8 and 72 hours, although xylazine overdoses on animals lasted up to 4 hours.

6. What are the signs and symptoms of an overdose of xylazine?

A person who has overdosed on xylazine will likely be unresponsive due to its sedative effects. A combination of xylazine and fentanyl can cause blue/greyish skin, slowed breathing, and slow heartbeats.

7. Is naloxone (Narcan) effective in reversing xylazine overdoses?

No.

An overdose of xylazine cannot be reversed with naloxone (Narcan). In the event of a suspected opioid-involved overdose, naloxone (Narcan) should still be administered since xylazine is almost always found in combination with opioids, including fentanyl.

8. Are skin ulcers caused by xylazine?

There appears to be an association between xylazine and skin ulcers, although the cause has not been definitively proven. As a result of the regular use of xylazine, it is common for people to develop severe skin ulcers and abscesses. The Philadelphia hospital system has reported an increase in skin and soft tissue infections since xylazine became more prevalent on the drug market.

9. Is it possible to experience withdrawal from xylazine?

Yes.

A person who uses xylazine heavily and frequently may experience withdrawal symptoms. There is often tension, anxiety, and irritability associated with xylazine withdrawal. In some cases, it can also cause a rapid heart rate and high blood pressure.

10. Is xylazine a controlled substance?

Currently, xylazine does not fall under the federal Controlled Substances Act (CSA).