Severe Fentanyl Withdrawal Associated With Medetomidine Adulteration: A Multicenter Study From Philadelphia, PA

Severe Fentanyl Withdrawal Associated With Medetomidine Adulteration: A Multicenter Study From Philadelphia, PA

Published: March/April 2026
Journal Article

Overview

This one-hour, journal article–based activity details the emergence of medetomidine, a potent veterinary α2-adrenergic agonist, as a dangerous adulterant in the illicit fentanyl supply. The article characterizes a novel, severe withdrawal syndrome that is distinct from standard opioid withdrawal, often requiring intensive care and aggressive α2-agonist therapies. This review is important for clinicians to recognize and manage this high-acuity syndrome as it spreads beyond initial geographic hotspots. 

The target audience for this intermediate continuing education activity includes physicians, nurse practitioners, physician assistants, and other clinicians, researchers, students, and policymakers. 

This activity addresses the following ACGME Core Competencies: Patient Care, Medical Knowledge, Practice-Based Learning and Improvement, and Systems-Based Practice 

Abstract

Aims 

Medetomidine, a potent veterinary α2-adrenergicagonist, has emerged as an adulterant in the illicit fentanyl supply in Philadelphia, PA. Accompanying this change, a severe withdrawal syndrome, distinct from opioid and more comparable to dexmedetomidine withdrawal, emerged. We describe it.

Methods

A multicenter case series is described across 3 hospital systems in Philadelphia between September 2024 and April 2025. The cohort included patients who reported opioids as the primary drug of choice, who presented with opioid withdrawal complicated by severe sympathetic activation and required hospitalization. Data extraction from the electronic health record included demographics, clinical outcomes, and confirmatory toxicology in a subset.

Results

Two hundred nine patients met the inclusion criteria; the median age was 38 years, and 29% were female. Intensive care unit (ICU) admission occurred in 77.5%, with 20.1% requiring intubation. Symptoms were often refractory to traditional opioid withdrawal management, and 73.7% received dexmedetomidine infusion. In the cohort subset with toxicology testing (n = 43), 100% had fentanyl and medetomidine metabolites, while xylazine metabolites were not always present (24, 55.8%). Severe complications included encephalopathy (35.4%), myocardial injury (28.7%), and rarely seizures (5%). Patients suffered from severe withdrawal, with a median maximum recorded Clinical Opiate Withdrawal Score (COWS) score of 23.

Conclusion

This study describes individuals experiencing severe withdrawal, temporally associated with medetomidine-adulterated fentanyl exposure. Clinicians should be alert to the limitations of standard withdrawal protocols for fentanyl or opioids and the need for aggressive α2-agonist therapies, such as dexmedetomidine. As medetomidine continues to spread in the illicit drug supply, adapting clinical and public health responses will be critical.

Learning Objectives

Upon completion of this activity, learners will be able to:

1. Differentiate the clinical presentation of medetomidine-adulterated fentanyl withdrawal from standard opioid withdrawal, specifically identifying signs of severe sympathetic hyperactivity.   
2. Identify the limitations of traditional opioid withdrawal protocols (e.g., COWS-based buprenorphine induction) when treating patients exposed to medetomidine. 
3. Determine appropriate escalation of care and pharmacological interventions, such as dexmedetomidine infusions, for patients presenting with refractory autonomic instability. 

Registration Rates

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Open Registration: 03/19/2026 - 02/10/2029

Close Access Date: 02/10/2029

Course Instructions

1. Click on the Contents tab to begin this activity.
2. Click Download Journal Article in the box titled Journal Article and read the journal article in its entirety. 
3. Click Complete Post-Test to answer multiple-choice questions. You will have 10 attempts to pass and must answer 2 out of 3 questions correctly.
4. Click Complete General Evaluation to provide valuable activity feedback. Scroll down on all questions, as there may be answer options that expand past the size of the window.
5. Click the button Claim Medical Credits in the box titled Claim Credits & Certificate. Choose the type of credit and click submit. Click the button View/Print Certificate to save or print your certificate. You can view/print your certificate at any time by visiting the ASAM eLearning Center, clicking Dashboard, and clicking Transcript/Achievements.

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Accreditation & Credits

Joint Accreditation Statement

In support of improving patient care, the American Society of Addiction Medicine is jointly accredited by the Accreditation Council for Continuing Medical Education (ACCME), the Accreditation Council for Pharmacy Education (ACPE), and the American Nurses Credentialing Center (ANCC), to provide continuing education for the healthcare team.

Credits Available

• Physicians: 1.00 Credit
• Nurses & NPs: 1.00 Nursing Contact Hour
• PAs: 1.00 Credit
• Interprofessional Continuing Education: 1.00 Credit
• Certified Counselors: NBCC Contact Hours Not Offered

  

  American Society of Addiction Medicine has been approved by NBCC as an Approved Continuing Education Provider, ACEP No. 7062. Programs that do not qualify for NBCC credit are clearly identified. American Society of Addiction Medicine is solely responsible for all aspects of the programs.

Maintenance of Certification (MOC)/Continuing Certification Program (CCP)

This activity is designed to meet the requirements for MOC/CCP for several primary physician boards and for state licensing CME requirements. MOC Credit is only reported and designated for ABA, ABP, ABIM, and ABS. By completing the online credit application and evaluation, the learner permits ASAM to report credits to the appropriate Board. Learn more.

• ABIM MOC Points: 1.00 Medical Knowledge
• ABP MOC: 1.00 Lifelong Learning & Self-Assessment
• ABS Continuing Certification: 1.00 Accredited CME
• ABA MOCA 2.0®*: 1.00 Lifelong Learning MOCA 2.0® is a trademark of the American Board of Anesthesiology®. This activity contributes to the CME requirement for Part II: Lifelong Learning and Self-Assessment of the American Board of Anesthesiology's (ABA) redesigned Maintenance of Certification in Anesthesiology Program® (MOCA®), known as MOCA 2.0®. Please consult the ABA website, https://www.theaba.org/, for a list of all MOCA 2.0 requirements.

Additionally, this activity has been designed to satisfy the requirements of the following primary physician board certification requirements. Please confirm with your individual Board.

• American Board of Addiction Medicine (ABAM)
• American Board of Preventive Medicine (ABPM)
• American Board of Psychiatry and Neurology (ABPN)
• Royal College of Physicians and Surgeons of Canada (RCPSC)

Certificates for other professions

All participants may request a certificate of participation upon completion of the activity and an online evaluation confirming their participation. Learners are strongly advised to contact their professional licensing board or professional association to confirm this certificate will be accepted as evidence supporting continuing education requirements.

California Association for Drug/Alcohol Educators (CAADE)

This educational program is approved by CAADE: #CP40 999 1225.

California Association of DUI Treatment Centers (CADTP)

This educational program is approved by CADTP: #205.

California Consortium of Addiction Programs and Professionals (CCAPP)

This educational program is approved by CCAPP: #OS-20-330-0227.

Disclosure Information

In accordance with the disclosure policies of ASAM and Joint Accreditation, the effort is made to ensure balance, independence, objectivity, and scientific rigor in all accredited continuing education activities. These policies include identifying and mitigating all relevant financial relationships with ineligible companies for those involved in the creation and dissemination of accredited continuing education. 

See the attached article and pdf for a list of disclosures