Copyright The Philadelphia Inquirer
Dominic Cipriano couldn’t stop shaking. A drug dealer on the streets of Kensington had sold him a bag of what he thought was fentanyl. But whatever Cipriano had taken didn’t produce the familiar rush of the opioids he’d been using on and off since he was a teenager. And when he entered withdrawal, he started rocking from side to side, wracked by uncontrollable tremors. “I was like, ‘What the hell is that from?’” he said. Cipriano was experiencing the effects of a powerful veterinary tranquilizer, called medetomidine, never approved for human use. It causes sedation so intense that users commonly black out, followed by a constellation of withdrawal symptoms that can be life-threatening. He began using medetomidine this past spring, around a year after public health officials first detected it in opioids sold on the street. By early 2025, medetomidine was showing up in 70% of the illicit opioid samples tested in Philadelphia, alongside other unregulated sedatives, industrial chemicals, and synthetic opioids like fentanyl. Local health officials were still working to understand the drug scene’s last major threat, an animal tranquilizer called xylazine and known on the street as “tranq,” which had been leaving thousands of drug users with gaping flesh wounds, sometimes even exposing bones. Medetomidine, the officials learned, does not appear to cause the skin lesions that xylazine does. But as with xylazine, physicians worried about a sharp rise in dangerous withdrawal cases — and uncertainty about its long-term effects. “With xylazine, when we saw so many people suffering from amputations, I hazarded that there really wasn’t anything worse,” said Kory London, the director of clinical operations at Jefferson Methodist Hospital. “But I think we have found something worse.” With xylazine, when we saw so many people suffering from amputations, I hazarded that there really wasn’t anything worse. But I think we have found something worse.” Kory London, director of clinical operations at Jefferson Methodist Hospital As officials scrambled to understand the new threat, Philadelphians struggling with opioid addiction were finding out in real time. Drug users would lose consciousness on the street, with their heart rates dropping. The paramedics who found them tried dispensing naloxone, a medication used to reverse opioid overdoses, but couldn’t wake them up. In withdrawal, they would shake and vomit uncontrollably, gripped by intense pain that traditional medications couldn’t soothe. Their blood pressure spiked, putting them at risk of heart attacks and other life-threatening complications. The impact was being felt in hospital emergency rooms citywide, where the number of patients visiting for withdrawal complaints rose threefold — from 800 to nearly 2,400 — in the year that ended this spring, according to Philadelphia Department of Public Health data obtained through an open-records request. It is not clear how many of those cases were medetomidine-related, although the department has linked the rise in ER visits to the drug’s sudden ubiquity. Philadelphia’s rapidly changing and increasingly toxic drug supply often acts as a bellwether for other U.S. cities. The city was among the first to see overdose deaths spike after fentanyl, a potent synthetic opioid, emerged last decade, and has spent the last five years trying to respond to xylazine. Dealers have moved on to new additives so fast that medical professionals have struggled to keep pace with treatment. But with medetomidine, doctors and addiction medicine providers rapidly mobilized to track symptoms and develop new protocols for treating them as quickly as possible. Within a month of first taking medetomidine, Cipriano knew that he had to seek help. Addicted to a drug he never wanted to use, he was blacking out on the street, barely stirring even when police officers tried to shake him awake. In withdrawal, he would vomit, jerk, and sweat. More than a dozen times this year, he experienced what he described as seizures — sometimes directly after he used drugs, sometimes after the effects wore off. Cipriano doesn’t know what caused the seizures, but suspects some bags of drugs he bought contained higher levels of medetomidine. But he worried that doctors wouldn’t be able to help him. It was a concern that his half-sister, Diamond Stahl, has lived and worked with every day. Stahl, who has been in recovery for three years, once used drugs with her brother on the streets of Kensington. Now working at Penn Medicine as a certified recovery specialist, she has struggled to help clients navigate an addiction treatment system unequipped to handle the latest drug threat. Traditional addiction treatment options — inpatient rehabs and detox clinics — cannot dispense the powerful medications needed to ease medetomidine withdrawal. Hospitals can, but local doctors say that insurance companies won’t cover patients admitted to the hospital solely for opioid withdrawal. Caught in the middle, patients like Cipriano frequently avoid rehabs or leave once their withdrawal symptoms become too much to bear. But they typically won’t be admitted to hospitals until that withdrawal becomes life-threatening. This summer, Stahl kept an eye out for her brother as she made outreach rounds on the streets — promising him that, when he was ready, she’d help him get into treatment. She knew how hard the process would be. She also knew how dangerous it was for Dominic to stay on the streets. Sometimes, she texted him with a simple plea: “Please don’t die.” Dangerous withdrawal As soon as emergency rooms saw the rise in patients in severe withdrawal from drugs in spring 2024, doctors in Philadelphia began the search for answers. Brendan Hart, an emergency physician at Temple Health, recalls examining a patient in the hospital’s intensive care unit in late summer whose blood pressure was spiking. The man’s heart was racing, and he had become incoherent and so agitated that he had to be placed in physical restraints. Doctors were treating him with heavy doses of sedatives that are typically used to help patients in withdrawal from alcohol and benzodiazepines. But the man was not responding to the medication. His medical chart showed that he regularly used opioids, though his symptoms did not match a typical opioid withdrawal. Hart had read the city’s warnings that medetomidine had shown up in the illicit opioid supply. And several overdose patients at Temple had recently tested positive for the drug. Hart was familiar with a similar sedative, marketed as Precedex, that is approved for humans and generally used only in ICU settings. When patients are not weaned off it properly, it causes some of the same withdrawal symptoms as medetomidine. Doctors typically give patients withdrawing from illicit opioids a controlled dose of a safer opioid-based medication, like methadone, to treat their initial withdrawal symptoms. Then, doctors slowly decrease the dose, keeping patients comfortable. Under close ICU supervision, Hart decided to try the same approach with a combination of opioids and Precedex. Within a day, the man improved. Hart saw the same results with several other patients in similar conditions treated at Temple over the next few months. He shared his success story with doctors at other area health systems, who were connected through meetings organized that summer by the city health department to discuss a rise in unusual withdrawal cases. We’re really throwing the kitchen sink [at it].” A Penn doctor at a November 2024 meeting with peers from Jefferson and Temple By November 2024, doctors from Penn, Jefferson, and Temple were comparing notes on medetomidine treatment options — from Precedex to ketamine infusions to blood-pressure medications like clonidine. “We’re really throwing the kitchen sink [at it],” one Penn doctor said, according to meeting minutes obtained by The Inquirer. In May, area physicians shared their experiences with medetomidine and its treatment in a Centers for Disease Control and Prevention report. Three of the city’s major health systems identified at least 165 patients admitted to their hospitals in a five-month stretch, beginning in September 2024, who were likely suffering from medetomidine withdrawal. Ninety-one percent of that cohort were so ill they required treatment in intensive care units. The physicians warned that other emergency departments should note the developing situation in Philadelphia and start testing their area’s drugs for medetomidine. In June, Philadelphia health officials released a set of guidelines on how to treat medetomidine’s withdrawal symptoms, including recommendations to try Precedex and clonidine. Nine months had passed between the identification of the new drug hazard and the release of an official guidance on treating it. This turnaround time is hailed as a grim victory in a city that had seen more than 10,000 people die of overdoses in the last decade. “This is the fastest I’ve seen evidence change clinical practice,” said Danny Teixeira da Silva, the medical director at the city health department’s Division of Substance Use Prevention and Harm Reduction. Lessons from the past Teixeira da Silva credited the rapid response to lessons learned the hard way in the mid-2010s after fentanyl, a deadly synthetic opioid, replaced heroin in Philadelphia’s drug markets. For the next decade, deaths soared in the region, and fentanyl remains the leading cause of overdose deaths in Philadelphia. A few years ago, xylazine emerged. Suppliers could buy the animal tranquilizer online for as cheap as $6 a kilogram. Opioid traffickers began adding the tranquilizer to fentanyl as a “filler” that extended users’ short-lived high — and increased dealers’ profits, according to the U.S. Drug Enforcement Administration. Within five years, the severe skin lesions associated with xylazine use had created a new public health crisis: Amputations among people addicted to opioids had doubled in Philadelphia. In 2024, state officials tried to make it harder for dealers to access xylazine by making it a controlled substance, limiting who can purchase it. Several other states have also placed limits on xylazine purchasing. Between 2024 and 2025, emergency rooms saw the number of opioid-addicted patients with skin infections drop by more than half, city health records show. Why and how medetomidine emerged so rapidly in the nation’s increasingly unpredictable drug supply is unknown. Some have theorized that difficulties obtaining xylazine led traffickers to search for another tranquilizer to add to illicit drugs. “It’s a lot of speculation, but I think suppliers made an effort to find another substance that had similar effects, that wasn’t a controlled substance, that could be mixed in or disguised as a white powder,” said Phil Durney, a physician who heads Jefferson Health’s inpatient addiction services. I think suppliers made an effort to find another substance that had similar effects, that wasn’t a controlled substance, that could be mixed in or disguised as a white powder.” Phil Durney, a physician who heads Jefferson Health’s inpatient addiction services Or traffickers might be searching for more potent drugs to market to customers who have developed high tolerances for tranquilizers, said Alex Krotulski, a director at the Center for Forensic Science Research and Education, a Horsham nonprofit that works with public health officials to test drug samples and identify trends. Medetomidine first appeared in Philadelphia drug markets on the same spring weekend that it was first detected in Chicago, Krotulski said. “Medetomidine’s proliferation across the U.S. has been a lot faster than xylazine,” he said. “It’s only been around as an adulterant for about a year, and at this point we’ve seen it in all regions of the United States.” As with xylazine, tracking cases is challenging, in part because there are no medical billing codes associated with medetomidine or its side effects. Medetomidine also leaves a person’s body quickly, making it difficult to track through drug tests. Medetomidine was detected in about 15% of all fatal overdoses in Philadelphia between May 2024 and May 2025, according to preliminary city data obtained by The Inquirer. Still, it’s unclear whether medetomidine is driving deaths, which have declined citywide in the last two years. Medetomidine’s withdrawal symptoms can mimic other health conditions, like a heart attack. Doctors are also concerned about the long-term effects of medetomidine withdrawal on patients who experience dangerous swings from low to high blood pressure. “We’ve certainly seen a number of patients who we’ve suspected of having, essentially, brain damage from the high blood pressure,” Jefferson’s London said. He and his colleagues have begun giving patients at Methodist, the system’s South Philadelphia hospital, low doses of Precedex outside the ICU in an effort to free up space there and treat more patients. “You can see within a matter of a few hours that a patient’s symptoms are improving,” Durney said. ‘I’m scared of what’s out there’ When Stahl first heard rumors of a new drug circulating in Philadelphia’s drug market a year ago, she immediately feared for her brother. Cipriano and Stahl, who share the same father, grew up in a Delaware County family with many relatives struggling with addiction. They began using drugs as teenagers; by adulthood, they were living on the street in Kensington. Even at their lowest moments, they supported each other. Diamond loved how Dominic could always make her laugh; how, even when he had no permanent home, he carried around a suitcase full of self-help books. Dominic marveled at his sister’s compassion and drive, especially after she entered recovery three years ago. Stahl had started addiction treatment in Mississippi but relapsed and returned to Kensington, where the potency of the drugs on offer shocked her. She ended up overdosing in a 7-Eleven; an employee revived her with naloxone. “I had a revelation,” she said. “I’m going to die.” The increasing toxicity of Philadelphia’s drug supply — xylazine was becoming ubiquitous in the illicit drug market at the time — steeled her resolve to stay sober in the early days of her recovery. If I’d just waited a few more months to get help, my life could look a lot different from it did.” Diamond Stahl “I’m scared of what’s out there,” she said. “If I’d just waited a few more months to get help, my life could look a lot different from it did.” Cipriano was still caught in an addiction cycle. Though he’d gone long stints without using drugs before, by this summer, Cipriano had been in active addiction for three years. When Cipriano was on the streets, Stahl stayed in touch with him, looking for him whenever work took her to Kensington, where he slept in abandoned buildings in between stints in shelters. “When you love someone, you don’t care what condition they’re in — you help them anyway,” Stahl said. “God forbid, if anything ever happened to him, do I want the last memory I have of him to be me shunning him?” Cipriano said his sister is the only person from his family he’s still in touch with. “I don’t go around my family at all — I’m embarrassed,” he said. “Seeing her makes me feel normal, for that little bit of time.” A vicious cycle “We don’t want to do this stuff,” Cipriano said. “But we’re so scared to stop.” Medetomidine withdrawal, doctors say, has trapped many patients in a vicious cycle. The medications available for withdrawal at detox programs and rehabs are limited. Many use opioid-based addiction medications like buprenorphine to ease patients’ symptoms, but the more effective Precedex generally can be used only in a hospital ICU. Yet patients in withdrawal typically are not admitted to hospitals until they are experiencing life-threatening symptoms. Sam Stern, an addiction medicine physician at Temple, recalled a patient who dropped by the health system’s mobile clinic, a van that regularly stops in Kensington to treat clients on the streets. “He had made repeated attempts to go into drug treatment, but the withdrawal was too severe. Really, it was only when he got transferred to the hospital and got stabilized that he was able to stop using drugs,” Stern said. When you love someone, you don’t care what condition they’re in — you help them anyway. God forbid, if anything ever happened to him, do I want the last memory I have of him to be me shunning him?” Diamond Stahl of her brother Dominic Cipriano Stahl has seen many patients enter rehab only to return to the streets within days. And she watched her brother struggle even after a recent hospitalization, where he received Precedex as treatment for medetomidine withdrawal. After leaving, he went right back to using drugs. Last month, Cipriano’s ongoing drug use landed him at Penn Presbyterian Medical Center. The cocktail of withdrawal medications he received, including Precedex, were still barely enough to treat his symptoms, he said. “It wasn’t touching the surface,” he said. But his medical team’s support helped him endure the withdrawal symptoms, he said. “They spent extra time with me, connected with me. I started to think differently,” he said. When he left the hospital, he went back to Kensington. He thought about using drugs again. He thought about spending another winter on the streets. And he decided to take a step he’d spent years avoiding: He approached paramedics and asked them to take him to an inpatient rehab program. Several days into recovery, he was still experiencing lingering withdrawal symptoms on Monday, but they were slowly subsiding.
