Xylazine (pronounced as ZY-leh-zeen) is a worldwide popular veterinary drug used to sedate animals. It’s sometimes used together with ketamine – by vets who need anesthesia for horses, cattle, and other big mammals. Xylazine is a non-opioid anesthetic and the structural clone of clonidine.
It was never meant to be used by humans; however, applied science has changed in recent years. Its popularity on the streets of the USA and even Europe is growing fast. The slang name of this drug is “tranq” on the streets. Dealers adulterate their drugs, heroin or fentanyl, with it to make the mixture stronger and cheaper. However, this combination can cause severe side effects and is often fatal. In April 2023, xylazine-laced fentanyl was called “an official emerging drug threat to the nation.”
In this article, we will explain everything about xylazine. Want to know its origins, mechanism of action, veterinary uses, reasons for being used by drug dealers, side effects, and dangers of abuse? All of this is there.
What is Xylazine?
Xylazine is a non-opioid drug used as a sedative and anesthetic, primarily in veterinary medicine. It’s a powerful receptor agonist that works very quickly. Xylazine is very close to clonidine by its structure. In the latest years, this drug has become popular on the streets of the world and is misused by humans.
Some Historical Context
Xylazine was first discovered by Bayer in Leverkusen, Germany, in 1962 as a drug to lower blood pressure. However, studies on humans showed dangerous xylazine side effects, including hypotension and bradycardia. That is why it was not approved for human use. However, tests on various animals show that it’s useful and effective for sedation, anesthesia, pain relief, and muscle relaxation.
Is Xylazine a Controlled Substance?
Xylazine is a prescription veterinary drug. However, it’s not – and never was – regulated as a controlled substance (under the Controlled Substances Act). As practice shows, people can buy it online through distributors, sometimes even without a need to show a veterinary license.
The FDA (Food and Drug Administration) did not approve xylazine for human use. It has harmful side effects on heart rate and blood pressure.
Brands, Composition, and Forms of Xylazine
Xylazine, as a veterinary drug, is sold under the brand names Rompun, Sedazine, AnaSed, and Chanazine. The most famous one is Rompun, made by Bayer Company. By the way, this company created Xylazine.
The most popular veterinary packages are 25 and 50 ml, with a 100 mg/mL concentration. Each milliliter contains:
- 100 mg Rompun (xylazine base equivalent, a thiazine derivative)
- 0.9 mg methylparaben
- 0.1 mg propylparaben
- Water for injection
- Citric acid and sodium citrate for pH adjustment
You can also find Xylazine in other concentrations, like 20, 200, and 300 mg/mL. All veterinary forms of xylazine are liquid. It comes ready for injections that can be done intramuscularly or intravenously.
Illegal Markets
When traded as an illicit drug or drug adulterant, xylazine can be found in various forms, including pills (fentanyl+xylazine, mostly) and even powder. You can even buy yourself a kilogram of xylazine on some suspicious Indian or Chinese website, and no license will be required. The typical price was $10-$20 a few years ago; now it has grown to $40-$50 per kilogram.
At this low price, its use as an adulterant increases the profits for illicit (and dishonest) drug traffickers. The psychoactive effects of xylazine allow reducing the amount of expensive fentanyl or heroin used in a mixture. As a result, drug abusers get a relatively low-cost drug that can harm their health even more than just fentanyl alone.
Xylazine Uses: For Animals
Sedation and Anesthesia in Animals
Vets commonly use xylazine to sedate animals before procedures that require immobilization or reduced responsiveness. They often combine it with other anesthetics, such as ketamine or something else. This can enhance its efficacy and provide perfect anesthesia for an operation.
Pain Relief and Muscle Relaxation
Beyond sedation, xylazine offers significant analgesic effects. This factor is valuable for managing pain, both during and after surgical interventions. Its muscle-relaxant properties are very useful in procedures that require muscle relaxation – examinations, orthopedic procedures, etc.
Common Species Treated
It is approved for use in a variety of animal species, including Xylazine for horses, cattle, elk, deer, and even dogs and cats – in smaller quantities, of course. It is used before minor surgical procedures and acts very fast, in minutes. The effects are related to depression of the central nervous system.
Moreover, it has its usage during scientific research – we’re talking about animal experiments. Xylazine is a component of a very popular anesthetic, ketamine-xylazine, known as a “Rodent cocktail”. It works wonders to anesthetize hamsters, rats, mice, and guinea pigs.
What Is Xylazine Used For? – Human Use and Abuse
Xylazine has become a very popular thing on the streets. Its common slang name is “tranq,” but when mixed with fentanyl, it’s known as “sleep-cut,” “zombie drug,” “iso,” and “tranq dope.”
How and Why Do People Use It?
Drug users often mix xylazine with other street illegal drugs—for example, fentanyl or benzodiazepines. Then they inject, consume orally, or even inhale it.
The question “Why do they do this?” is far more complex. Some people use it because xylazine makes a drug high last longer. On the other hand, the high from fentanyl is relatively short. Xylazine may be added by some users to extend it, as well as to mimic the high of heroin.
But most people who consume drugs don’t even know that there is xylazine in their dope. Drug traffickers use it as a perfect substance, cheap and white, to adulterate expensive heroin or fentanyl. During one research in 2022, xylazine was found in over 90% of drug samples in Philadelphia. So, people may have been aware of fentanyl dangers—but not of xylazine ones. We will discuss them below in more detail.
Xylazine Abuse Trends and Cases
- In 1979, the first case of xylazine toxicity was reported. A 34-year-old male tried to self-cure insomnia with an injection of xylazine. He used 1 gram of it and was hospitalized after that. The man survived.
- Some years after that, drug dealers began to adulterate drugs with xylazine, and people began to die from its scary side effects. One of the first cases of mass mortality was in Puerto Rico. From 2002 to 2008, 53 people died from xylazine in the local prison in Guerrero. The tendency has never stopped.
- As of 2012, typical xylazine users in Puerto Rico were mostly males under 30. They were living in a rural area, or they were homeless. One more: they preferred injecting the illegal drug rather than inhaling it. However, after the drug’s surge in popularity, it became difficult to look for any patterns among users.
- In the latest years, the number of lethal overdoses involving xylazine has grown even more in the U.S. It increased from 102 in 2018 to 3,468 deaths in 2021, according to an analysis by the CDC. Federal officials said that xylazine is a fast-growing threat.
- In April 2023, the Biden administration officially called xylazine-laced fentanyl “an emerging drug threat to the nation.”This was the first time such a label was given in American history. Rahul Gupta, the ONDCP Director, called the effects of the fentanyl-xylazine “devastating.” He described this drug as the deadliest threat the U.S. has ever encountered.
- In July 2023, xylazine caused the first death outside of North America—in Solihull, England. Later, in 2024, British cops found this drug in illicit THC e-cigarettes.
- In April 2024, Seattle police reported a new danger. They confirmed that “tranq” was sold as a standalone narcotic.
Xylazine Mechanism of Action
In terms of pharmacology, Xylazine is an adrenergic receptor agonist. What does that mean, you ask? It stimulates the adrenergic receptors in body tissues.
How exactly does it work? The drug reduces norepinephrine and dopamine release in the central nervous system. It does so by mimicking norepinephrine. In simple terms, it says, “Hi, I’m norepinephrine; I’m here; no need to produce more!” to the receptors. They send this signal to the brain: “No more norepinephrine, please.” As a result, your body slows the production of this hormone, and it results in heavy sedation.
Xylazine absorbs and spreads all over the body very fast, in minutes. Full steam ahead—at the cost of harmful side effects. It’s affecting the heart, lungs, liver, and kidneys. The sedative effects usually start within 15–30 minutes and can last up to 4 hours.
What’s interesting – this drug also crosses the famous blood-brain barrier with ease due to its chemical properties. Factors like sex, diet, and health conditions may influence its effects on a person.
Xylazine Side Effects and Risks
Immediate Effects on the Human Body
As we’ve said before, xylazine acts incredibly fast after entering the human (or animal) body. It acts as a central nervous system depressant, leading to rapid and powerful sedation. Users may experience a heavy, prolonged “nod,” sometimes rendering them unconscious. When in combination with fentanyl or another drug, symptoms can vary.
Acute Effects of Xylazine
The acute effects of xylazine misuse are severe. Individuals often feel extreme drowsiness, significantly slowed breathing, and a decreased heart rate. This is what xylazine was meant to do. These symptoms are dangerous and can be even fatal. It depends on the dose and the combination of drugs in the dope. Some users experience:
- Blurred vision
- Asthenia
- Dysarthria
- Tachycardia
- Drowsiness
Chronic Misuse: Devastating Effects
Chronic misuse of xylazine leads to very dangerous physical consequences. The most famous of them are “xylazine skin wounds”—severe skin ulcers and abscesses. In worst cases, they can progress to tissue necrosis. You can find photos of these wounds on the Internet. But be warned—they are horrible, and not for the faint of heart.
These wounds often appear at injection sites but can also develop in other areas. If a person does nothing, they may lead to serious infections, sepsis, or necessitate amputation.
Other side effects for “tranq” chronic abusers may be diabetes, hyperglycemia, apnea, urinary incontinence, and ataxia. There are cases of coma caused by xylazine mixed with other drugs.
Mental Health Impacts
Beyond physical harm, xylazine misuse may seriously affect mental health. Prolonged use may lead to disorientation and memory loss. Dependence on it may cause anxiety and other mental health disorders.
Addiction and Abuse Potential of Xylazine
Xylazine appears to worsen the effects of other drugs. Combining this drug with fentanyl or heroin increases the risk of death. Xylazine leads to sedation, respiratory depression, and bradycardia. When mixed with opioids, these effects intensify and can be fatal. Moreover, overdoses of xylazine are difficult to identify, as they often are similar to opioid overdoses. A common drug screening test will not find this substance if the doctors aren’t looking for it purposefully.
Chronic use of xylazine can lead to physical dependence and tolerance. Over time, users may require higher doses to achieve that “sedated high.” And, as you can guess, it increases the chances of getting a severe side effect like diabetes or coma.
Withdrawal
Xylazine withdrawal is very hard to treat. It’s often marked by irritability, powerful anxiety, and a feeling of unease. And that extreme anxiety can last for months! It may also cause a rapid heart rate and high blood pressure. There is some clinical guidance on managing xylazine withdrawal, but not very much. The doctors are developing their knowledge ASAP, trying to keep up with xylazine “trends.”
Symptoms of Xylazine Overdose
Xylazine overdose presents distinct and severe symptoms. Profound sedation is common, so heavy that people become unresponsive. Bradycardia, hypotension, and respiratory arrest are those critical signs. And these symptoms can quickly lead to fatal outcomes. So, overdose prevention is really important.
Challenges in Identifying It
Just defining this substance overdose is difficult. “Tranq” is not an opioid, but it is often mixed with such substances. This complicates the diagnosis, as the symptoms resemble those from opioids. Standard drug testing may not detect xylazine, making the work of doctors even more difficult.
Xylazine Treatment and Its Limitations
Xylazine overdose management focuses on symptomatic care. As you can understand, it’s not that effective. The medics have to monitor cardiovascular and respiratory functions. And they are going to it, ready for mechanical ventilation of the lungs. Respiratory failure is a common thing that happens to xylazine abusers.
No Antidote
What’s even worse – as of 2025, xylazine has no approved antidote for human use. And naloxone, a helpful thing for opioid overdoses, does nothing to xylazine. Moreover, the presence of “tranq” often makes naloxone less effective. But the doctors still administer naloxone in these scenarios, and they do it for a reason. Xylazine is almost always in combination with opioids, so naloxone can still have some effect.
Rehab & Addiction Treatment
Traditional withdrawal medications are useless in this case. So, detoxification is primarily supportive. The staff of rehab programs focuses on managing symptoms, support, and recovery. There is plenty of time for it—xylazine withdrawal can last for months. Finding a good support & recovery group like NA will certainly help in this way.
The Bottom Line
Xylazine, a useful and powerful veterinary sedative, brings lots of severe risks when misused by humans. Its sedative effects amplify opioid overdose potential. This mixture leads to devastating health consequences often – fatal ones. Just the xylazine wounds can kill a person, not to mention its effects on the heart and lungs.
When we are talking about xylazine, rehabilitation is critical. It’s very important for people who suffered from “tranq”, for their families, and for communities impacted. There is no magical pill to cure xylazine effects. So, if you face this challenge – find a good rehab center near you. Comprehensive treatment approaches, increased awareness, and community support are your top priorities!
Don’t try to walk this path alone—reach out for some support. Whatever treatment approach you choose, having the support of friends and family is invaluable. Just as the trusted support system in a good clinic. And always remember—you can do everything that you really want!
