Medetomidine is stronger than ‘tranq’ with severe and sometimes deadly withdrawals.
Medetomidine, a powerful new “zombie drug” known as “rhino tranq,” has reached California.
The California Department of Public Health (CDPH) stated in an email to The Epoch Times that the agency is aware of four medetomidine-related overdose deaths in 2025, an agency spokesperson said. She noted that the data is preliminary and more cases could be identified.
“The four medetomidine-related overdose deaths were associated with fentanyl, however CDPH does not have data on the extent to which medetomidine may be mixed with fentanyl in the drug supply,” the spokesperson said.
No overdose deaths linked to medetomidine were reported in the state during prior years, according to the department.
Jacqui Berlinn, co-founder of San-Francisco-based Mothers Against Drug Addictions and Deaths (MADAAD), told The Epoch Times in a text that she is horrified by the inhumanity of introducing an even more potent veterinary tranquilizer to fentanyl without regard for the lives of people struggling with addiction.
“This is what keeps mothers awake at night. There is a special cruelty in adding a drug like medetomidine to fentanyl,” she said. “As a mother who understands addiction, I see this for what it is: an escalation that shows complete disregard for human suffering and human life. I am horrified by the cruelty behind adding an even more powerful drug to an already dangerous supply. This isn’t accidental. It’s reckless disregard for human life.”
Medetomidine, first found in Philadelphia’s drug supply in May 2024, is 100 to 200 times more potent than xylazine—known as “tranq”—and can cause longer-lasting sedation, low heart rates, and more severe withdrawal symptoms. It is not an opioid but is found in the street opioid supply, according to the Philadelphia Department of Public Health (PDPH).
Medetomidine, like xylazine, is called a “zombie drug,” which describes the behavior of users experiencing its heavy sedative effects. Both medetomidine and xylazine are animal tranquilizers not meant for human use, according to CDPH.
Concurrent use of fentanyl and veterinary tranquilizers is associated with severe and necrotic skin and soft tissue injuries, which complicate treatment.
Xylazine was first found in illicit street drugs in Philadelphia in 2006, and by 2023 was detected in nearly all fentanyl tested by PDPH. But since the increase of medetomidine, there has been a corresponding decrease in the prevalence of xylazine in Philadelphia’s drug supply.
In December 2024, PDPH released a health alert notifying providers of severe withdrawal symptoms requiring intensive care unit level of care attributed to concurrent use of medetomidine and fentanyl.
In May 2025, the CDC reported that 165 patients were admitted to Philadelphia’s health systems between Sept. 1, 2024, and Jan. 31, 2025, with a newly recognized medetomidine withdrawal syndrome. Of those patients, 91 percent were admitted to an intensive care unit, and 24 percent were intubated, according to PDPH.
By Brad Jones
