What You Should Know About Xylazine

What to know

  • Xylazine is a non-opioid sedative or tranquilizer.
  • It is being found in the US illegal drug supply and linked to overdose deaths.
  • Many people may not be aware of the presence of xylazine, which makes it dangerous.


A tranquilizer called xylazine, a non-opioid sedative, is increasingly being found in the US illegal drug supply and linked to overdose deaths.1 Xylazine—which is not approved for use in people and can slow down the brain and breathing, make the heart beat slower, and lower blood pressure in people, is especially dangerous when combined with opioids like fentanyl.2

Due to its impact on the opioid crisis, fentanyl mixed (adulterated) with xylazine was declared an emerging threat by the White House's Office of National Drug Control Policy. On July 11, 2023, the White House released a National Response Plan to address the emerging threat of fentanyl mixed with xylazine.

This guide answers some common questions about xylazine, xylazine use, and overdoses involving xylazine. This page is not intended to give medical advice, clinical guidance, or treatment protocols.

What is xylazine?

Xylazine (also called "tranq" or "tranq dope") is a non-opioid sedative or tranquilizer. Although not a controlled substance in the United States, xylazine is not approved for use in people.3

What are symptoms and health risks of xylazine?

When used in people, xylazine can cause:

  • Sedation
  • Difficulty breathing
  • Dangerously low blood pressure
  • Slowed heart rate
  • Wounds that can become infected
  • Severe withdrawal symptoms
  • Death

How are people exposed to xylazine?

Illegal drugs such as cocaine, heroin, and fentanyl can be mixed with xylazine, either to enhance drug effects or increase street value by increasing their weight.45 People who use illegal drugs may not be aware of the presence of xylazine. DEA has seized xylazine and fentanyl mixtures in 48 of 50 states, and the DEA laboratory system reported that approximately 23% of fentanyl powder and 7% of fentanyl pills seized by the DEA in 2022 contained xylazine.6 Xylazine is usually injected, although it can be swallowed or sniffed.3

Should naloxone be given in the case of an overdose involving xylazine?

Naloxone should be given in response to any suspected drug overdose to reverse any possible opioid effects. Naloxone will not reverse the effects of xylazine.7 However, because xylazine is often used with opioids like fentanyl, naloxone should still be given. It's important to call 911 for additional medical treatment, especially since the effects of xylazine may continue after naloxone is given.

What should be done for someone with signs and symptoms of a possible opioid overdose or an overdose involving opioids and xylazine?

  • Give naloxone. Naloxone can reverse the effect of any opioids and will not cause harm if opioids are not involved in an overdose However, because naloxone will not address the impact of xylazine on breathing effects of xylazine may continue after naloxone is given.
  • Call 911. Stay with the person until first responders arrive. Overdose is a medical emergency. First responders can assess the situation and provide treatment.
    • Good Samaritan laws are in place in most states to protect those who are overdosing and anyone assisting them in an emergency from arrest, charges, or a combination of these.
  • Give rescue breaths. First responders have reported that rescue breaths are especially helpful for people who have used xylazine because use causes breathing to slow down.89 To give rescue breaths to adults, make sure the person's airway is clear; place one hand on the person's chin, tilt the head back, and pinch the nose closed. Place your mouth over the person's mouth to make a seal and give two slow breaths. Watch for the person's chest (but not the stomach) to rise and follow up with one breath every 5 seconds.

How can people who use illegal drugs reduce harms of xylazine and overdose involving opioids and xylazine?

For people who use illegal drugs, the following strategies can help reduce the risk of overdose.

  • Never use alone. A trusted contact can help reduce overdose risk by giving naloxone and calling 911 in case of an emergency. People who don't have a trusted contact nearby can take advantage of services that allow people to seek non-judgmental support over a phone or video call when they are using drugs. Never Use Alone is a nationwide service that connects callers to trained volunteers who will gather basic information about the caller's location, stay on the line to support the caller if they plan to use substances alone, and alert 911 if the caller becomes unresponsive.
  • Carry naloxone and learn how to use it. Because xylazine is often mixed with opioids like fentanyl, naloxone should be given in response to a suspected overdose to reverse any possible opioid effects. Importantly, naloxone will not reverse effects of xylazine. In the event of an overdose, call 911 for additional medical treatment.
  • Provide rescue breaths. Rescue breaths are especially helpful for people who have used xylazine since xylazine causes breathing to slow down.89 Harm reduction experts also suggest rolling individuals on their side, into the recovery position.1011
  • Know the risks of using illegal drugs with unknown ingredients. Illegal drugs are unregulated—they don't come with an ingredients list. As a result, dosage and purity are difficult to determine. Heroin, fentanyl, and cocaine may be mixed with xylazine or other substances. Counterfeit pills that closely resemble prescription medications and contain illegal substances are increasingly common in the illegal drug market.12
  • Seek medical care for skin wounds. Skin wounds may become infected and worsen quickly. When treated early, wounds can be managed with basic wound care techniques. If left untreated, wounds can lead to amputation or become life threatening.6
  • Reduce injection-related risks. According to the National Harm Reduction Coalition, the risk of infection can be reduced by using sterile injection equipment, rotating injection sites, allowing skin and veins time to heal before another use, and taking drugs in other ways besides injection.
  • Test drugs before using. There are commercially available test strips to test for the presence of xylazine in a sample of drugs. Fentanyl test strips can be used to test opioids, stimulants, or prescription medications for fentanyl.13 When people have knowledge that their drugs contain fentanyl, they can take steps to reduce their risk of opioid overdose.

How can communities reduce harms of xylazine and opioids/fentanyl mixed with xylazine?

Community-based organizations and public health departments:

  • Educate the public about the increasing presence of xylazine in the drug supply and how to respond to suspected xylazine-involved injuries and overdoses.
  • Raise awareness of the changing illegal drug marketplace and the common use of illegally made fentanyl with other drugs like xylazine.
  • Provide messaging to community groups (particularly those providing services to people at higher risk), community leaders, school officials, faith-based leaders, parents, students, and others about the changing illegal drug supply and risks for exposure to strong opioids like fentanyl or fentanyl mixed with xylazine.

Harm reduction organizations:

  • Call 911 immediately after recognizing an overdose or resuscitating a patient. Naloxone available in the field may not be enough to reverse a fentanyl-involved overdose, and in the case of fentanyl mixed with xylazine, symptoms associated with xylazine may continue after naloxone is given. More than one dose of naloxone may be required to restore normal breathing, and in cases involving xylazine, rescue breaths should be given.
  • Provide test strips for people who use drugs as part of community drug checking programs. These are key opportunities to educate people who use drugs about the increasing presence of xylazine. This also provides an opportunity to educate and encourage people who use drugs about how to use various harm reduction strategies.
  • Link people who are at risk for overdose with care and track their retention in care programs, including wound care.
  • Increase overdose prevention education and take-home naloxone to people who use drugs, their friends, and others likely to witness or experience an overdose.14151617
  • Partner with public safety and public health to obtain and disseminate the latest information on local drug supply and overdose trends.1819

First responders to overdoses:

  • Consider xylazine as a contributor to overdose when naloxone administration is ineffective.20
  • Provide rescue breaths. Rescue breaths are an especially helpful intervention for people who have used xylazine since use causes breathing to slow down.89

Healthcare providers:

  • Talk to patients about the changing illegal drug supply and risks for overdose and exposure to highly potent opioids like illegally made fentanyl and fentanyl mixed with xylazine.
  • Counsel patients to call 911 and that naloxone will not reverse the effects of xylazine. In the event of an overdose involving fentanyl and xylazine, naloxone should still be given, but it's important to note that the effects of xylazine may continue after naloxone administration. Reiterate the importance of calling 911 after naloxone has been administered for an overdose involving fentanyl and xylazine.
  • Provide active referral to treatment and care options and recovery support services,21 including wound care.
  • Implement post-overdose response protocols that incorporate links between public health, treatment providers, community-based service organizations, and healthcare professionals. These protocols promote overdose education, treatment, linkage to care, and medications for opioid use disorder and naloxone distribution.2223

Data on xylazine and overdoses

The presence of xylazine in drugs tested in labs increased in every region of the United States from 2020-2021, with the largest increase in the South.4 Studies from specific areas found similar increases. One study from 10 US cities showed xylazine was involved in less than 1% of drug overdose deaths in 2015 and in nearly 7% in 2020.8 In samples from eight syringe services programs in Maryland tested between 2021 and 2022, xylazine was found in almost 80% of drug samples that contained opioids.24 In Philadelphia, Pennsylvania, xylazine was found in 31% of overdose deaths involving heroin and/or fentanyl 2019.25

In a recent study from CDC's State Unintentional Drug Overdose Reporting System (SUDORS), among 20 states and Washington D.C., the monthly percentage of deaths involving illegally made fentanyl (IMF) with xylazine detected increased from 3% in January 2019 to 11% in June 2022.26 During January 2021–June 2022 in 31 states and Washington D.C., xylazine was detected in a higher percentage of IMF-involved deaths in the Northeastern U.S.26

  1. Kariisa M, Patel P, Smith H, Bitting J. Notes from the field: xylazine detection and involvement in drug overdose deaths—United States, 2019. Morbidity and Mortality Weekly Report. 2021;70(37):1300.
  2. FDA alerts health care professionals of risks to patients exposed to xylazine in illicit drugs November 8, 2022. https://www.fda.gov/drugs/drug-safety-and-availability/fda-alerts-health-care-professionals-risks-patients-exposed-xylazine-illicit-drugs
  3. Thangada S, Clinton HA, Ali S, et al. Notes from the field: xylazine, a veterinary tranquilizer, identified as an emerging novel substance in drug overdose deaths—Connecticut, 2019–2020. Morbidity and Mortality Weekly Report. 2021;70(37):1303.
  4. Drug Enforcement Administration. The growing threat of xylazine and its mixture with illicit drugs. 2022. https://www.dea.gov/sites/default/files/2022-12/The%20Growing%20Threat%20of%20Xylazine%20and%20its%20Mixture%20with%20Illicit%20Drugs.pdf
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  14. O'Donnell J, Gladden RM, Mattson CL, Hunter CT, Davis NL. Vital Signs: Characteristics of Drug Overdose Deaths Involving Opioids and Stimulants — 24 States and the District of Columbia, January–June 2019external icon. MMWR Morb Mortal Wkly Rep 2020;69:1189–1197.
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