The drop in overdose deaths may be the result of more veterinary tranquilizers – and less fentanyl – in street drugs

More people who use illicit substances are becoming heavily sedated and sometimes suffering fatal complications in hospitals, rather than dying outside, experts say.

Christopher Moraff, founder of the statewide drug-checking program PA Groundhogs, tests a bag of 'dope' in Philadelphia in 2023. A highly-potent veterinary tranquilizer, not approved for human use, is leading to intense sedation and withdrawal among people who use drugs, the city's health department warns.
Courtenay Harris Bond/PhillyVoice

Drug overdose deaths have been dropping precipitously at the local and national level, new statistics show. But the data does not capture the intensified symptoms complicating withdrawal management in Philadelphia – and may not accurately reflect the number of people who are dying from drug-related causes, say people with boots on the ground.

Deaths from drug overdoses declined nationwide by 17% between July 2023 and July 2024, from 113,000 to 94,000 deaths, according to data released Wednesday by the Centers for Disease Control and Prevention. Pennsylvania's drug overdose deaths decreased by more than 24%, from 5,195 to 3,937. In New Jersey, they fell by just under 24%, from 3,009 to 2,288. 


MORE: Philly's 'dope' is ever changing, and that poses challenges for health care workers on the front lines

The most current statistics from the Philadelphia Department of Public Health show a 7% decline in drug overdose deaths between 2022 and 2023 – the first drop in five years. They fell from 1,207 to 1,122.

At the same time, the city health department has noted an increase in the use of animal sedatives in illicit drugs sold as "dope," "tranq" or "tranq dope" – marketed as containing opioids – over the past few years. Medetomidine, a highly-potent animal tranquilizer not approved for use in humans, has surpassed xylazine, a lower-potency veterinary tranquilizer, the city's health department warned in a Dec. 10 alert. The health department first detected medetomidine in the drug supply in May.

The intense tranquilizing effects of xylazine and medetomidine have caused more sedation, but not as many overdose deaths compared to when fentanyl – an opioid about 100 times more potent than morphine and 50 times more potent than heroin – dominated the drug supply. And recent overdose death statistics do not account for people who are dying of blood infections and other medical conditions resulting from the increasingly poly-chemical, unpredictable nature of illicit drugs, locals who test the contents of street drugs said.

"Say I revive you, and you go to the hospital and die of brain failure," said Sarah Laurel of Savage Sisters, a Philadelphia harm reduction organization. "They classify that as brain failure, not anything related to drugs, which is not helpful for the cause. … I do believe that this poly-chemical substance wave is going to see an increase in drug-related deaths that won't be calculated through a specific drug overdose on the scene."

Nationwide, overdose deaths involving fentanyl accounted for approximately 80% of drug deaths in 2022 – a year when a record number of people — nearly 108,000 — died from drug overdoses, according to statistics from the National Institute on Drug Abuse. Philadelphia also saw a record number of drug fatalities in 2022 – 1,413 – 83% of which involved opioids, "almost always fentanyl," according to the city's health department.

But Philadelphia is now in a "fentanyl drought," said Christopher Moraff, who founded and runs PA Groundhogs, an organization that tracks the makeup of Pennsylvania's illicit drug supply in conjunction with the Center for Forensic Science, Research and Education based in Horsham. In early 2023, a bag of dope in Philadelphia contained about 18% pure fentanyl, compared to about 7% now, Moraff said.

"We have a drug supply that is loaded with all kinds of stuff like xylazine and medetomidine that may have some nasty side effects, but acute fatal toxicity is not one of them," Moraff said.

The latest CDC statistics are "probably reflecting the extreme proportions of xylazine as opposed to fentanyl," Moraff said. 

The statistics lag, so they would not account for the effects of medetomidine in illicit drugs, Moraff said.

Laurel said more medetomidine in drugs means "there are less people who are experiencing near fatal overdoses, and more people just heavily sedated. But there are other other things that are happening. We're seeing body tremors, seizures and hallucinations and psychosis, and we believe that those are all side effects from this very volatile poly-chemical substance wave."

Hospitals are reporting a "rapid transition from intoxication to withdrawal" in people who use drugs, complicating triage of patients and "requiring intensive care unit (ICU) level of care," the city's health alert warned.

People who work for Savage Sisters – which runs a series of recovery homes and does outreach, overdose reversal training and drug-checking – still carry naloxone, the opioid reversal medication also known by its brand name, Narcan. But mostly they are providing respiratory support through rescue breathing and oxygen bags to people heavily sedated from medetomidine who go into distress on the street, Laurel said.

With the recent plummet in fentanyl purity in dope bags, fatal drug overdoses may decrease even further, Moraff said.

"We probably will also see as an increase in car accidents, people walking into the street, sexual assault – all kinds of things that go along with somebody being incapacitated and sedated," Moraff said.

In this week's alert, the Philadelphia health department cautioned that:

• Symptoms of worsening and severe withdrawal include intractable vomiting, excessive diaphoresis, hypertensive emergency, waxing and waning hypoactive encephalopathy, tremor and tachycardia.

• Although opioid withdrawal is often safely managed in outpatient, residential and non-hospital treatment settings, adulterants such as medetomidine may necessitate higher levels of care for intoxication, withdrawal management and may require hospital or ICU-level support.