|
Summary:
Maricopa County Department of Public Health (MCDPH) has confirmed three fatal overdoses involving the illicit drug adulterant medetomidine. All three overdoses occurred in January 2026, and also involved fentanyl. Deaths were identified using toxicology results from medicolegal death investigations, which often take a few months to finalize. These reports are consistent with the Health Advisory issued by CDC and the White House Office of National Drug Control Policy (ONDCP) on April 2, 2026, which raises awareness of increasing reports of detection of medetomidine in at least 18 states but also warns about severe withdrawal syndrome due to medetomidine exposure.
Medetomidine is a short-acting alpha-2 agonist used as a non-opioid sedative and is more potent than xylazine. Medetomidine (also known as 'rhino tranq,' 'mede,' or 'dex') is not approved for human use but is approved for sedation and analgesia in dogs. Healthcare providers should be aware of this potential exposure in the Maricopa County illicit drug supply and should consider potential medetomidine toxicity or other polydrug intoxication when patients presenting with suspected opioid overdose experience prolonged sedation even after adequate opioid overdose reversal medication administration (OORMs; e.g., naloxone).
Clinical Presentation of Medetomidine Intoxication:
- Reported symptoms include significant bradycardia (heart rate as low as 32 beats per minute); hypotension; and persistent sedation despite OORM applications.
- Potential medetomidine toxicity mixed with other polydrug intoxication (such as fentanyl) may produce altered mental status, pinpoint pupils, and hypoxemia.
- Consider potential medetomidine toxicity or other polydrug intoxication when patients presenting with suspected opioid overdose experience prolonged sedation continuing even after adequate OORM administration.
- Unlike xylazine, medetomidine use does not seem to be associated with development of wounds.
- The frequency of respiratory support and intensive care unit (ICU) management for medetomidine-involved overdoses is comparable to that for opioid or stimulant overdoses not involving medetomidine, unless withdrawal signs are present.
Clinical Presentation of Medetomidine Withdrawal Syndrome:
- Stopping medetomidine following regular use can precipitate a severe withdrawal syndrome, similar to clonidine withdrawal, that can require emergency or intensive care. Withdrawal symptoms are marked by tachycardia (>100 beats per minute); severe hypertension; fluctuating alertness; tremor; chest pain; and intractable nausea and vomiting.
- Complications of withdrawal can include non-ST elevation myocardial infarction and posterior reversible encephalopathy syndrome.
- Refer to emerging guidance for best practices on managing medetomidine withdrawal.
- Consider observing patients with suspected prolonged periods of heavy medetomidine use for signs of medetomidine withdrawal for several hours after last use. While withdrawal symptoms peak at 18-36 hours after last use, patients who do not show signs of medetomidine toxicity or withdrawal within 6-12 hours are less likely to experience severe withdrawal.
Additional Actions That Healthcare Providers May Take:
- While medetomidine is not widely available on drug screening panels, consider advocating for the validation and addition of medetomidine to comprehensive drug screening panels.
- Please continue to include illicit substance information and naloxone administration information in the chief complaint section of Emergency Department notes.
Resources:
CDC Medetomidine Situation Summary
DEA Medetomidine and Dexmedetomidine
CDC Health Alert Network Medetomidine April 2026
Penn Medicine Emerging Guidance for Managing Medetomidine Withdrawal
CDC Webinar: Clinical Implications of Medetomidine Mixed with Opioids
Thank you for your continued collaboration and partnership.
Maricopa County Department of Public Health
|
