xylazine
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What is xylazine?
Xylazine is a drug used in veterinary medicine as a sedative, pain reliever, and muscle relaxant for animals including cats, dogs, cattle, and horses.
Though not intended for human use, it is sometimes added to illicit drug combinations, like heroin and fentanyl, to prolong euphoric effects. Xylazine can cause dangerously low heart rate, respiration, blood pressure, and body temperature in humans, possibly leading to coma or death. Other complications include skin lesions, pressure ulcers, blood clots, and severe withdrawal symptoms. Because it is not an opioid, naloxone does not reverse its effects.
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For what purpose is xylazine used in animals?
Xylazine is a veterinary drug used to sedate animals, relieve pain, and induce muscle relaxation. It is an alpha-2 adrenergic receptor agonist that reduces the release of adrenergic substances in the central nervous system, which causes analgesia, muscle relaxation, and sedation. Veterinarians commonly use xylazine in animals such as cats, dogs, cattle, and horses for surgery and other clinical purposes. It may also be used in wildlife like deer and elk. Though it was initially tested for use in humans, it was found to have excessive and life-threatening effects.
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How does xylazine work in the bodies of animals?
Xylazine, a veterinary drug, acts as an alpha-2 adrenergic receptor agonist. Within the central nervous system, it diminishes the release of adrenergic substances, such as epinephrine and norepinephrine. These neurotransmitters usually trigger the fight-or-flight response; therefore, xylazine reduces their levels, resulting in analgesia, muscle relaxation, and sedation. Vets commonly use it to sedate animals such as cats, dogs, cattle, and horses for clinical purposes and surgery. Xylazine was initially tested as a blood pressure-lowering agent in humans, but, due to excessive and life-threatening effects, it was adapted for animals instead.
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Which types of animals commonly receive xylazine, and why?
Xylazine is a veterinary drug used to sedate, relieve pain, and induce muscle relaxation in animals. It is an alpha-2 adrenergic receptor agonist that reduces the release of adrenergic substances in the central nervous system, resulting in analgesia, muscle relaxation, and sedation.
Veterinarians commonly use xylazine in animals such as cats, dogs, cattle, and horses, as well as in wildlife like deer and elk, typically for surgery and other clinical purposes.
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What are some possible side effects of xylazine in animals?
Xylazine is a veterinary drug used to sedate, relieve pain, and induce muscle relaxation in animals such as cats, dogs, cattle, horses, deer, and elk.
Xylazine is an alpha-2 adrenergic receptor agonist. It reduces the release of epinephrine and norepinephrine, which usually mediate the fight-or-flight response. When xylazine lowers the levels of these neurotransmitters, analgesia, muscle relaxation, and sedation occur.
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Why is xylazine sometimes a concern if it is found outside of veterinary use?
Outside of veterinary applications, xylazine is a concern because it is used as an adulterant in illicit drug combinations. It is often mixed with opioids like fentanyl and heroin to prolong euphoric effects.
Xylazine can cause dangerously low blood pressure and body temperature, slowed heart rate and respiration, deep sedation, coma, and even death in humans. It can also cause severe skin lesions, and those who use it may develop a physical dependence, with withdrawal symptoms including seizures and sharp chest pains. Because it is not an opioid, naloxone, which is used to treat opioid overdoses, will not reverse xylazine's effects.
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xylazine, drug used in veterinary medicine to sedate, relieve pain, and induce muscle relaxation in animals. Xylazine was discovered in 1962 by researchers at the German pharmaceutical company Farbenfabriken Bayer AG (now Bayer AG). The drug was initially investigated for its antihypertensive (blood pressure-lowering) properties in humans. However, because its effects were found to be excessive and life-threatening in human subjects, it was instead adapted for use in animals. Nonetheless, xylazine is highly sought after as an adulterant in illicit drug combinations for human use, particularly in mixtures containing opioid drugs (e.g., heroin and fentanyl), since it prolongs the euphoric effects produced by opioids. Xylazine is frequently detected in persons who have died from drug overdose.
Mechanism and veterinary use
Xylazine is classified as an alpha-2 adrenergic receptor agonist. In the central nervous system, its action at these receptors reduces the release of so-called adrenergic substances—namely, the neurotransmitters epinephrine and norepinephrine. Epinephrine and norepinephrine normally mediate the “fight-or-flight response,” and thus when their levels are decreased by the actions of xylazine, analgesia (pain relief), muscle relaxation, and sedation occur. Veterinarians typically use xylazine to sedate animals for surgery and other clinical purposes. It is commonly used in cats, dogs, cattle, and horses but may also be used in wildlife such as deer and elk.
Illicit use
In humans, xylazine causes deep sedation. Specifically, it slows heart rate and respiration and decreases blood pressure and body temperature, which can drop to dangerously low levels that result in a coma or death. In addition to life-threatening effects on major organs, other medical complications, such as pressure ulcers and blood clots, can result from users’ lying in the same position for long periods of time. In addition, xylazine causes skin lesions that resemble blisters, as well as small scabs and areas of dead tissue. These wounds usually appear on the arms and legs or at the injection site but may also be apparent elsewhere on the body; they may also develop in users who have snorted or smoked the drug. Some cases are so severe as to require limb amputation. Furthermore, individuals who use xylazine may develop a physical dependence on the drug; withdrawal symptoms can be severe and typically include sharp chest pains and seizures.
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In the early 2000s, laboratory testing conducted by the U.S. Drug Enforcement Administration (DEA) found that xylazine had been used as an adulterant in drug mixtures in Puerto Rico, where it was later also found to be used on its own. The drug, in its illicit form, was first detected on the U.S. mainland in 2006. By 2022 the DEA had seized mixtures of xylazine and fentanyl in 48 states. Overdose deaths involving xylazine increased in parallel with the spread of the drug. Because xylazine is not an opioid, the administration of naloxone, which relieves potentially fatal respiratory depression caused by opioid overdose, does not reverse its effects.