As I’ve noted here before, I have a friend who is a retired Philadelphia detective who worked the streets of Kensington before turning in his badge a few years ago.

The former detective took me on a couple of macabre evening tours of Kensington’s open-air drug market and the open-air drug user’s street lounge in past years. I recall seeing the stooped, staggering, and squatting drug addicts inhabiting the sidewalk amidst trash and garbage.

It looked to me like a scene from “The Walking Dead.”

While smoking a cigar recently with the former detective, I mentioned that, having earlier walked past Broad and McKean Streets in South Philadelphia, I was reminded of the drug scene in Kensington. Like Kensington, Broad Street sports a small army of Walking Dead drug addicts.

My friend shook his head sadly and said that if one thought things could not get worse in Kensington and other parts of the city, think again.

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My detective friend spoke of “tranq,” also called the “zombie drug,” which is the most recent harmful drug appearing regularly on the streets of Philadelphia. He said that tranq, an animal tranquilizer, causes flesh-eating sores as well as respiratory depression.

He also alerted me to a federal update on xylazine, known on the street as “tranq.”

The Drug Enforcement Administration (DEA) and the Department of Homeland Security (DHS) issued a joint update on xylazine on Sept. 22.

According to the DEA and DHS, the White House Office of National Drug Control Policy (ONDCP) designated fentanyl adulterated or associated with xylazine as an emerging threat to the United States.

Xylazine is a powerful non-opiate sedative, analgesic, and muscle relaxant that has only been approved by the U.S. Food and Drug Administration for veterinary use. However, xylazine has been increasingly identified as a cutting agent/adulterant in the illicit drug supply, often mixed with fentanyl, which increases the risk of fatal drug poisoning.

“DEA and DHS have identified xylazine intended for illicit human use entering the U.S. in several ways: in solid form from China and other countries, in liquid form either diverted from veterinary supply chains or packaged to resemble a veterinary drug, and, to a lesser degree, mixed with fentanyl seized at the southwest border,” the joint update stated.

The Feds also stated that xylazine has also been detected in a growing number of overdose deaths. It is commonly encountered in combination with fentanyl but has also been detected in mixtures containing cocaine, heroin, and a variety of other drugs. Xylazine is most frequently reported in combinations with two or more substances present.

“Limited scientific research has been conducted on the effects of xylazine on the human body, but anecdotal reports indicate that users experience effects similar to opioids. Xylazine can lead to depression of the central nervous system along with other adverse effects, as reported in scientific and medical journals. The presence of xylazine in illicit drug combinations and its detection in fatal overdoses may be more widespread than reported, as a number of jurisdictions across the country may not include xylazine in forensic laboratory or toxicology testing.”

The Feds first took notice of xylazine as an adulterant in Puerto Rico in the early 2000s through DEA reporting and laboratory analysis. Around a decade later, it was documented on the island as a drug of abuse on its own, which has continued to present. In licit sales for veterinary use, xylazine is available in liquid form and sold in vials or preloaded syringes. These solutions are prepared at a concentration appropriate for administration by injection based on the general size and weight of the species. It is legitimately sold directly through pharmaceutical distributors and internet sites catering to veterinarians.

“However, xylazine is also readily available for purchase on other internet sites in liquid and powder form, often with no association to the veterinary profession or requirements to prove legitimate need. A kilogram of xylazine powder can be purchased online from Chinese suppliers with common prices ranging from $6 to $20 U.S. dollars per kilogram,” the Feds stated. “At this low price, its use as an adulterant may increase the profit for illicit drug traffickers, as its psychoactive effects allow them to reduce the amount of fentanyl or heroin used in a mixture. It may also attract customers looking for a longer high since xylazine is described as having many of the same effects for users as opioids but with a longer-lasting effect than fentanyl alone. Some users intentionally seek out heroin or fentanyl mixed with xylazine, while many are completely unaware it is included as an adulterant.”

Back in April, the Philadelphia Department of Public Health released a statement regarding xylazine.

“Dr. Rahul Gupta, Director of the White House Office of National Drug Control Policy, has announced officially designating fentanyl adulterated or associated with xylazine as an emerging threat to the United States,” the Health Department said. “Over the coming months, the ONDCP is convening an interagency working group to inform the development of the national response plan. The response will include work on xylazine testing, treatment, supportive care protocols, comprehensive data systems (including information on drug sourcing and supply), strategies to reduce the illicit supply of xylazine, and rapid research (such as work on the interactions between xylazine and fentanyl).”

In response to the White House announcement, Philadelphia Health Commissioner Dr. Cheryl Bettigole said, “We welcome the prospect of federal resources being brought to a problem causing deep harm to Philadelphians and look forward to working with federal agencies as the response plan rolls out.”

According to the Philadelphia Department of Public Health, xylazine has hit Philadelphia particularly hard, causing increased overdose deaths as well as severe wounds that can lead to sepsis and amputation.

“As a result, the Philadelphia Department of Public Health has been working closely with partners across the city to address this new aspect of the drug overdose epidemic. The Health Department has worked with local hospital systems and the Department of Behavioral Health and Intellectual Disability Services to develop practice-based standards for managing xylazine withdrawal to help prevent people with xylazine dependence from leaving treatment early due to uncontrolled symptoms.

“In collaboration with the Health Federation of Philadelphia and local experts, we are working to support wound care and to develop best practices for xylazine-associated skin wounds. The department has updated our overdose response trainings to incorporate the risk of fatal overdose associated with xylazine use and is developing communications for people who use drugs to increase awareness of xylazine. We are continuing to monitor the drug supply with surveillance drug checking and are planning to distribute xylazine test strips once we have them available. We are grateful to have a federal partnership on this work and look forward to the advances that a national focus on preventing further harm from xylazine can bring.”

As my friend the former detective noted, just when you thought the drug problem could not get worse, Philadelphia and the rest of the county are introduced to tranq, the flesh-eating zombie drug.

Paul Davis, a Philadelphia writer and frequent contributor to Broad + Liberty, also contributes to Counterterrorism magazine and writes the “On Crime” column for the Washington Times. He can be reached at pauldavisoncrime.com.