What Is Tranq (Xylazine)?

Medically Reviewed by Brunilda Nazario, MD on February 24, 2023
5 min read

As the U.S. opioid crisis continues, there’s a new lethal drug on the streets you’ll need to watch out for.

Xylazine, commonly known as “tranq,” is a non-opioid sedative analgesic medication that’s largely mixed into (adulterated) and used as an additive with other opioid substances like heroin, fentanyl, and cocaine. Blending tranq helps to bulk up and boost or mimic the effects of these drugs. As a matter of fact, tranq is now found in up to 15% of fentanyl tests.

But exposure to this mix of chemicals can have dangerous, potentially life-threatening effects on your health. It can cause such horrific wounds (necrotic skin ulcers) on your skin that it’s being dubbed a “zombie drug.”

Here’s everything you need to know about tranq and its effects.

Tranq was first made in 1962 by Bayer HealthCare Pharmaceuticals. It’s designed to be used as a central nervous system depressant. Veterinarians regularly use it to tranquilize (sedate), relieve pain, or as a muscle relaxant for animals like dogs, cats, and horses. It’s not FDA-approved for use in humans.

It’s typically sold as a clear liquid. In animals, the drugs kick into effect in just a few minutes and can last up to 4 hours. It’s sold under the brand name Anased, Chanazine, Rompun, and Sedazine.

Tranq is not a federally controlled substance. That means it’s not deemed illegal to use by itself under federal law. You can get it with a veterinarian’s prescription.

But laws around it are evolving and some states are tightening their laws around it. For example, New York passed a bill in 2017 designating xylazine as a controlled substance that is illegal to use or sell.

Tranq found on the streets is largely mixed with heroin, fentanyl, or cocaine to enhance or modify the drug’s effects. It causes a similar “high” or euphoric feeling as opioids do.

When it’s mixed mostly with heroin and cocaine, the drug is called ”speedball.” Besides tranq or “zombie dope,” it’s referred to by other street names in the U.S. like “tranq dope” or “sleep cut.” In Puerto Rico, where xylazine has been known to be a part of the opioid supply since the early 2000s, it’s called “anestecia de caballo” or horse anesthesia.

People who use this contaminated drug get it into their bloodstream in ways such as:

  • Smoking
  • Snorting
  • Injecting
  • Swallowing
  • Inhaling

Traces of xylazine can be found within other drugs, too. This can include benzodiazepines, alcohol, gabapentin, methadone, and prescription opioids. Xylazine has been used in attempted sexual assaults, accidental or intentional poisoning, and drug abuse.

When you overdose on drugs that contain traces of tranq, it can cause dangerous side effects. In severe cases, overdosing can lead to death.

Exposure to tranq can look very similar to an opioid overdose. It can include:

  • Slowing down of the central nervous system
  • Sedation
  • Slow breathing
  • Low blood pressure (hypotension)
  • Slow heart rate (bradycardia)
  • Severe, painful skin ulcers (necrotic skin lacerations) and abscesses
  • Slowed wound healing
  • Frequent, persistent, or worsening skin infections
  • Eye problems like small pupils (miosis)
  • Low blood sugar (hypoglycemia)
  • High blood sugar (hyperglycemia)
  • Drowsiness
  • Amnesia

Severe skin ulcers are usually a result of injecting tranq. But regardless of where you puncture your skin with tranq, the gashes could show up on a different part of your body.

If you notice these symptoms, call 911 or head to the nearest hospital for immediate medical attention.

When humans overdose on tranq, reports show that the effects can last anywhere from 8 to 72 hours (3 days).

There are no simple or rapid drug tests to check for traces of tranq.

Currently, tranq does not show up on routine drug tests or toxicology screens used to detect opioids or other street drugs. Your doctor will need to use other methods of detailed screenings or bloodwork to detect the traces of xylazine in your system.

If you have severe skin lesions, your doctor will do a skin biopsy. They will remove a sample of your affected skin tissue and test it under a microscope to see what’s causing it. They can also do wound cultures, which involves taking a swab of your wound to check for germs that might be causing the infection.

Tests that can detect tranq are:

  • Thin layer chromatography
  • Gas chromatography-mass spectrometry

Unlike mainstream opioids like fentanyl or heroin, there’s no simple antidote for tranq exposure and overdose.

But since tranq is often mixed in with opioids, first responders will give naloxone (Narcan) injections to reverse the opioid’s effects. But naloxone doesn't work well for tranq exposure.

In fact, tranq can be so potent that you’ll need several doses of naloxone to reverse the effects of the opioids present in the tranq mixture and revive someone who’s been exposed. But it doesn't improve the breathing or heart issues that tranq causes. Also, if you develop withdrawal symptoms, there’s no medication to help with it.

If you’ve overdosed from tranq, you’ll mostly get supportive care. This means if you’re admitted to the hospital, they’ll give you fluids through your veins (IV fluids) and saline eye irrigation.

They‘ll monitor your blood sugar levels and blood pressure, give you electrolytes, run tests on your heart (EKG), give medications for your heart, and provide support for your breathing.

There are antidotes (atipamezole, yohimbine) for xylazine that vets use on animals, but they’re not FDA-approved for use in humans.

If you frequently use illicit substances like opioids, you might get exposed to or take tranq intentionally or accidentally. Because they can have such dangerous effects on your health, it’s important to use them safely.

The best thing to do is to educate yourself and be aware of opioids, street drugs, and how to manage serious side effects if you were to have them.

To do it safely and prevent overdoses, you should:

  • Ask questions about what the drug is, what cut it is, and where it came from.
  • Try not to use substances alone. Do it with a supportive friend who can check in on you or keep a close eye on side effects.
  • Always carry naloxone and learn how to use it.
  • Use clean needles.
  • Try the substances in small doses to see how you react.
  • Have a safety plan in place. For example, let somebody know you’re about to use tranq or other substances. Have someone call 911 for you and stay with you until medical help arrives. They won’t get into trouble for getting emergency medical help.
  • Let a close friend or family know about your whereabouts.

If you can’t have someone watch over you, try a hotline like Never Use Alone, which is available in English (800-484-3731) and Spanish (800-928-5330).

You can also call the Poison Control Hotline at 800-222-1222.