A drug is wreaking havoc in major cities of the United States, including Philadelphia, due to its 'skin-rotting' characteristics. The substance is Xylazine, and is commonly called the zombie drug, tranq or tranq dope. It has devastating effects on its users, and can rot their skin. 


The "flesh-eating" drug has been linked to thousands of overdoses across the United States occurring from the use of illicit drugs such as heroin and fentanyl, the New York Post reported. 


Here is everything you need to know about xylazine


Xylazine is a non-opioid veterinary tranquiliser not approved for human use, and has been linked to an increasing number of overdose deaths in the United States in the evolving drug addiction and overdose crisis, with the largest impact in the Northeast. 


History of xylazine and its link with overdose deaths


Xylazine first appeared in Philadelphia before migrating to San Francisco and Los Angeles, and was used for cutting heroin. 


Overdose deaths linked to xylazine have spread westward across the United States, research has shown.


The percentage of all drug overdose deaths involving xylazine increased from two per cent to six per cent in Pennsylvania, from 2015 to 2020, according to the National Institute of Health's (NIH's) National Institute on Drug Abuse. 


In 2020, xylazine was involved in 10 per cent of all drug overdose deaths in Connecticut, and 19 per cent in Maryland in 2021. 


In 2021, as many as 2,668 people in New York died of overdoses, the New York City Department of Health reported.


According to Substance Use Philadelphia, a dashboard which provides information on drug use trends in Philadelphia, over 90 per cent of dope samples tested in the city in 2021 contained xylazine. Illicit drugs, which produce intoxicating or euphoric effects, are called dope drugs. Dope drugs with tranq were first seen in Puerto Rico, but currently, it is being found in more and more places across the United States. 


According to a 2022 study published in the Journal of Analytical Toxicology, xylazine has been discovered in 36 states of the United States. 


In November 2022, illicit drugs such as fentanyl and heroin were found to be contaminated with xylazine, according to the US Food and Drug Administration (FDA). The FDA warned healthcare professionals of the possibility of xylazine inclusion in illicit drug overdoses, because naloxone, a medicine that rapidly reversed an opioid overdose, might not be able to serve as an opioid antagonist when the drugs are contaminated with tranq. 


Opioids are a class of drugs that work by interacting with opioid receptors in one's cells, and have pain-relieving properties. Opioids include the illegal drug heroin, fentanyl and pain relievers available legally by prescription, such as oxycodone, codeine, hydrocodone and morphine. 


Most drug overdose deaths linked to both xylazine and fentanyl involved additional substances such as heroin, alcohol, cocaine, benzodiazepines, methadone, gabapentin, and prediction opioids. 


The FDA also stated that healthcare professionals should continue to administer naloxone, of Narcan, for opioid overdoses, and in case patients do not respond to naloxone, or when there are signs and symptoms of xylazine exposure, such as severe, necrotic skin ulcerations, the professionals should consider xylazine exposure, and must provide supportive measures to the patients.


While xylazine has been approved by the FDA for use in animals as a sedative and pain reliever, it is not safe for use in humans and may result in serious and life-threatening side effects that appear to be similar to those commonly associated with opioid use. This often makes it difficult to distinguish opioid overdoses from xylazine exposure. 


Since it is not known if side effects from xylazine exposure can be reversed by naloxone, or if reversal agents regularly used in veterinary medicine are safe or effective in humans, they should not be used, the FDA has warned. 


Moreover, xylazine cannot be detected using routine toxicology screens, and hence, additional analytical techniques are required to detect xylazine when there is a possibility of the substance being involved in illicit drug overdoses. 


In January 2023, a woman from Philadelphia suddenly developed xylazine-specific symptoms near her opioid injection sites, The New York Times reported.


According to the National Institute on Drug Abuse, people report using xylazine-containing fentanyl to lengthen its euphoria-inducing effects. 


What symptoms does xylazine exposure lead to?


Xylazine has been associated with severe skin ulcerations and wounds, which spread and worsen very quickly, and are seen regardless of how people use it, be it smoking, snorting or injecting, according to Substance Use Philadelphia. Since it is very difficult for the wounds to heal on their own, it is important to seek medical attention when one spots such symptoms. The skin ulcerations and necrotic skin lesions could occur in areas of the body away from the injection site. 


Mixing xylazine with other opioids such as fentanyl or heroin, and central nervous system depressants such as alcohol or benzodiazepines increases the risk of life-threatening overdose. 


In a statement released in February 16, 2023, the San Francisco Department of Public Health said the San Francisco Office of the Chief Medical Examiner (OCME) has determined that four individuals who died of drug overdoses between mid-December 2022 and mid-January 2023 had low levels of xylazine in their systems. 


Xylazine is a central nervous system depressant that can cause drowsiness and amnesia, which refers to the loss of memories, and results in slow breathing, according to the National Institute on Drug Abuse. Xylazine can also cause the heart rate and blood pressure to decrease to dangerously low levels. 


The drug can cause excessive sleepiness and respiratory depression symptoms that appear similar to those associated with opioid use, as a result of which it is often difficult to distinguish opioid overdoses from xylazine exposure. Respiratory depression or hypoventilation is a breathing disorder characterised by slow, shallow and ineffective breathing, and happens when the lungs fail to exchange carbon dioxide and oxygen efficiently, leading to a buildup of carbon dioxide in the body. It is a dose-dependent side effect of opioid use, and generally occurs after administration of high doses of opioids.  


People repeatedly exposed to xylazine, knowingly or unknowingly, could have skin ulcers, abscesses and related complications. 


While experts recommend giving naloxone in the event of a suspected xylazine overdose, the opioid antagonist does not address the impact of xylazine on breathing because the latter is not an opioid. Therefore, experts believe that the growing prevalence of xylazine in the illicit opioid supply might render naloxone less effective for some overdoses. They also believe that xylazine could worsen the ongoing drug epidemic. Hence, emergency medical services should be alerted in the case of a suspected overdose.