This Week’s Focus: Early Warning in Action — Insights from the NDEWS Early Warning Network

The NDEWS Weekly Briefing curates emerging data and findings from across the Early Warning Network, which includes three core components: our Scientific Advisory Group (SAG), comprised of national experts and federal partners; our Sentinel Site Directors (SSDs), who lead local surveillance in key geographic regions; and our Community-Based Health Experts, who provide on-the-ground insights from populations most impacted by drug trends. Together, these contributors generate timely, multidisciplinary and impactful information, ranging from peer-reviewed research findings to local surveillance data. These contributions inform public health and research communities.

At the recent American Society of Addiction Medicine (ASAM) meeting, it was noted that the NDEWS original findings from Palamar JJ, Fitzgerald N, Carr TH, Cottler LB, Ciccarone D. paper - National and regional trends in fentanyl seizures in the United States, 2017-2023. Int J Drug Policy. 2025 Apr;138:104417 - had the highest Altmetric score in the world of any drug related peer reviewed paper in 2024.

This week’s NDEWS Briefing highlights the growing impact of the NDEWS network on topics that we have recently published on. Our goal is to present the most current information on emerging drug trends. We appreciate the efforts of our Network for continuously contributing to the field and protecting public health. 

A recently published Notes from the Field in Morbidity and Mortality Weekly Report (MMWR) by Huo et al., co-authored by NDEWS Philadelphia SSD Dr. Jeanmarie Perrone and NDEWS SAG member Dr. Alex Krotulski, describes a life-threatening withdrawal syndrome linked to medetomidine, a nonopioid veterinary sedative increasingly found in Philadelphia’s unregulated opioid supply. Between September 2024 and January 2025, 165 hospitalized patients across three Philadelphia health systems exhibited severe autonomic withdrawal symptoms—including hypertension and tachycardia—that were unresponsive to standard treatment for fentanyl and xylazine withdrawal but improved with dexmedetomidine. Medetomidine was detected in 72% of opioid samples in late 2024 and confirmed in patient toxicology.
Read the report here.

Related Content:
Watch the CAMP Webinar: Medetomidine in the Drug Supply (April 23, 2025) — Hosted by the Center for Addiction Medicine and Policy with clinicians from Temple University and Thomas Jefferson Hospital, this session reviews clinical management.

New Adulterants Report (Apr 2024–Feb 2025): Download from PA Groundhogs — a guide for people who use drugs, harm reductionists, and clinicians on emerging compounds like medetomidine.

A recently published short communication in Drug and Alcohol Dependence by Thakrar et al., co-authored by NDEWS Philadelphia SSD Dr. Jeanmarie Perrone, examined signs of potential xylazine withdrawal syndrome (XWS) in 121 hospitalized patients in Philadelphia with urine xylazine testing. Detection of xylazine was not associated with vital sign instability and was linked to lower odds of ICU admission. Structured chart review found no consistent or distinct signs of XWS across cases, suggesting that, unlike opioid withdrawal, physiologic dependence on xylazine may be rare or clinically indistinct from other co-occurring withdrawal syndromes. 
Read the report here.

A Centers for Disease Control and Prevention (CDC) investigation published in Morbidity and Mortality Weekly Report (MMWR), co-authored by NDEWS SAG member Dr. Alex Krotulski, identified 12 confirmed and 26 probable medetomidine-involved overdoses in Chicago in May 2024. Medetomidine was detected alongside fentanyl in all blood and drug samples tested. Most cases occurred among non-Hispanic Black men aged 45 to 64 years and were characterized by bradycardia and poor response to naloxone.
Read the report here.

What is Medetomidine? Medetomidine, also known as "Domitor®", is a highly potent alpha-2 adrenergic receptor agonist primarily used as a veterinary sedative and analgesic. Medetomidine has a rapid onset of action and produces significant sedative, amnestic, and analgesic effects.

What was found? Several sources in the NDEWS network have alerted to Medetomidine's inclusion in the opioid supply and harmful effects of medetomidine withdrawal. Reddit data shows a consistent increase in medetomidine since December, and discussions of this drug are at an all-time peak on Reddit.

Previous NDEWS Reports:
June 14th, 2024
April 11th, 2025

How is it being discussed? Online discussions suggest that medetomidine is used in combination with opioids for recreational purposes. Online discussions mention both intentional and accidental medetomidine use. Reddit users report that the drug's potent sedative effects are an order of magnitude greater than those of xylazine. The combined CNS depression of a fentanyl-medetomidine mixture, often referred to as "rhino tranq", is highlighted by commenters as a major danger, potentially leading to severe respiratory depression and overdose. The discussion also notes that the potency difference between medetomidine and other sedatives like xylazine may not be well understood, leading to unintentional overdoses. More recently there has been increased discussion about negative withdrawal symptoms, including tremors and cardiovascualar instability, that, in some cases, reportedly required intensive hospital care. Discussants also are referring to new symptoms more recently including hallucinations and peripheral cyanosis (blue skin without hypoxia) Recent discussion also notes the availability of medetomidine specific test strips.

Drug Terms: Medetomidine, Domitor®

An article in Prehospital Emergency Care by Rettger et al., co-authored by NDEWS SAG members Drs. Barry Logan and Alex Krotulski, describes the detection of medetomidine during a cluster of opioid overdoses in Worcester, Massachusetts. Using blood samples from two patients and advanced analytical toxicology conducted at the Center for Forensic Science Research and Education, the study identified medetomidine alongside fentanyl and xylazine. Clinical signs included bradycardia and hypotension, prompting dissemination of findings to emergency clinicians, health departments, and harm reduction organizations.
Read the article here.

Fentanyl Express, a five-part investigative series by Reuters and winner of the 2025 Pulitzer Prize, traces how chemicals from China fuel fentanyl production in Mexico and drive the U.S. overdose crisis. Featuring insights from NDEWS SAG member Dr. Alex Krotulski, the series explores chemical sourcing, trafficking routes, policy gaps, and the evolving role of antidotes like naloxone.
Read the article here.

A study in the International Journal of Drug Policy by NDEWS Co-Director Dr. Joseph Palamar, analyzed survey data from 3,332 New York City nightclub attendees between 2017 and 2024. Past-month ketamine use rose from 3.1% to 6.8% (a 118% increase), with the steepest increases among adults aged 26 and older, females, college graduates, and sexual minorities. Ketamine use was strongly associated with past-month cocaine (aOR=8.17), LSD (aOR=8.46), and MDMA (aOR=2.76) use.
Read the study here.

An article in Substance Use & Misuse by Chandler et al., co-authored by NDEWS SAG member Dr. Matthew Ellis, examined patterns of recreational ketamine use among individuals in treatment for opioid use disorder (OUD). Survey data from 301 treatment-seeking individuals revealed that 28.6% reported lifetime ketamine use, with motivations ranging from achieving a psychoactive effect (70.9%) to self-treatment for mental or physical health issues (46.4%), including opioid withdrawal symptoms. Ketamine use was more prevalent among younger males and those living in non-rural settings. Polysubstance use involving ketamine was common (70.7%), particularly with marijuana, alcohol, cocaine, MDMA, and opioids.
Read the article here.

A study in Substance Use & Misuse by Zinsli et al., co-authored by NDEWS SAG members Drs. Barry Logan and Alex Krotulski, tested dried blood spot (DBS) specimens collected from 1,345 participants at six syringe service programs across the US. Using a novel liquid chromatography–mass spectrometry assay developed at the Center for Forensic Science Research and Education, researchers detected regional patterns of drug use, including high methamphetamine positivity in Western states and elevated cocaine, fentanyl, heroin, and xylazine positivity in Eastern states. Half tested positive for more than one substance.
Read the study here.

A randomized trial in Drug and Alcohol Dependence by Stoops et al., including NDEWS SAG member Dr. Jennifer R. Havens, found that individuals with cocaine use disorder (n = 107) who received high-value contingency management showed reduced mean arterial pressure over 12 weeks, despite not achieving full abstinence. Overall, greater cocaine-negative urine samples were linked to decreased stromal cell-derived factor-1α (SDF-1α) and increased intercellular adhesion molecule-1 (ICAM-1) and neutrophil activating peptide-2 (CXCL7) biomarkers associated with endothelial repair and platelet activity.
Read the study here.

An article in the Journal of Analytical Toxicology by Lee et al., co-authored by NDEWS Texas SSD Dr. Dayong Lee, presents updated findings on phencyclidine (PCP)-positive driving under the influence (DUI) cases in Houston, Texas, from 2019 to 2023. Among 1,375 cases, the median blood PCP concentration remained stable at 45 ng/mL, and 59% involved polydrug use, most commonly cannabinoids (39%), cocaine/metabolites (15%), and ethanol (10%). The majority of drivers were male (77%) and Black (89%), and the mean age continued to increase from 38 years in 2019 to 43 years in 2023. These toxicological and demographic trends remained remarkably consistent with previous surveillance data from 2013 to 2018, highlighting the persistent prevalence of PCP-impaired driving in Houston.
Read the article here.

A study in Preventive Medicine Reports by Shrestha et al., co-authored by NDEWS Kentucky SSD Peter Rock, used four spatial analytic methods to evaluate changes in geographic accessibility to buprenorphine providers across Kentucky, Massachusetts, and Ohio between 2020 and 2022. The authors found that while geographic accessibility improved overall, particularly in urban areas and regions with higher baseline access, accessibility in rural communities remained limited. Although Kentucky’s Wave 1 HEALing Communities Study (HCS) intervention sites showed a greater increase in access than the state average, similar patterns were not observed in Massachusetts or Ohio.
Read the study here.

A dashboard from the University of Washington’s Addictions, Drug & Alcohol Institute, affiliated with NDEWS Seattle/King County SSD Dr. Caleb Banta-Green, presents January–March 2025 drug checking results across Washington state. Fentanyl and methamphetamine were most frequently detected, with notable findings of xylazine, novel opioids, and veterinary anesthetics in community-submitted samples.
View the dashboard here.

A recently reported law enforcement operation, submitted by NDEWS Community-Based Health Expert Dr. Robert Crecelius and described by KOB (NBC affiliate, Albuquerque), details the dismantling of one of the largest fentanyl trafficking networks in US history. Federal agents seized over 4 million fentanyl pills, $4.4 million in cash, 41 firearms, and nearly 80 pounds of methamphetamine, heroin, and cocaine. Couriers ran bulk deliveries on a near-daily basis to cities across the western US, including Denver, Phoenix, Las Vegas, Salem, and Layton.
Read the article here.

You are invited to attend the NDEWS Summit at the College on Problems of Drug Dependence (CPDD) 87th Annual Scientific Meeting on Saturday, June 14th (06/14/2025) from 4:00 pm - 6:00 pm CT in Bayside Ballroom AB, 4th floor. The Summit will be open to all CPDD meeting attendees. 

We hope to see you there!

NDEWS Posters and Presentations at CPDD

In June, the NDEWS team will be traveling to attend the 87th College on Problems of Drug Dependence (CPDD) Annual Meeting in New Orleans, Louisiana. Along with posters, the NDEWS team will be presenting a late-breaking abstract, an oral presentation and two invited symposia. We invite you to join us for these presentations. Please find the presentation information below:

Sunday, June 15
3:30 pm - 4:45 pm CT Late-Breaking Abstract
Anesthetics (“-Caines”) Adulterate the Illicit Fentanyl Supply: A National Drug Early Warning System (NDEWS) Alert
Joseph Palamar, Joshua DeBord, Alex Krotulski, Bruce Goldberger

5:00 pm - 6:30 pm CT Poster Session 1 (Napoleon Ballroom CD, 3rd Floor)
Trends in Nonfatal Fentanyl Poisonings Involving Stimulants in the United States, 2015–2023
Nicole Fitzgerald, Joshua Black, Linda Cottler, Silvia Martins, Joseph Palamar

Monday, June 16
10:45 am - 12:15 pm CT Invited Symposium
Found in Translation: Coordinated Preclinical, Human Laboratory and Epidemiological Approaches to Understanding Polydrug Use
William Stoops, Lori Knackstedt, Linda Cottler, Christa Corley

3:30 pm - 4:30 pm CT Oral Session: Sex Matters: Translational Evaluations of Sex-Specific Factors in Substance Use
Sex Differences in Problematic Substance Use, Mental Health, and Social Determinants of Health among Middle-Aged and Older Adults in the All of Us Research Program
Vijaya Seegulam, Bia Whipp, Liva LaMontagne, Linda Cottler

5:45 pm - 7:15 pm Poster Session 2 (Napoleon Ballroom CD, 3rd Floor)
Natural Language Processing Analysis of 7-Hydroxymitragynine Reddit Discussion
Daniel Van Zant, Kirsten Smith, Oliver Grundmann, Catherine Striley, Elan Barenholtz, Christopher McCurdy, Linda Cottler

Tuesday, June 17
3:45 pm- 4:45 pm CT Oral Presentation at Mini Symposium: Prevalence and Characteristics of Recreational Ketamine Use among Nightclub Attendees and College Students in the New York Tristate Area.
The Current Landscape of Medical and Recreational Ketamine Use
Shahar Almog, Meredith Berry, Joseph Palamar 

5:30 pm - 7:00 pm CT Poster Session 3 (Napoleon Ballroom CD, 3rd Floor)
Reported Use of Recreational and Medical Cannabis, Delta-8, and Delta-10: Findings from NDEWS Sentinel Sites and Hotspots (2022–2023)
Tamara Millay, Vijaya Seegulam, Monica Bhargavi Kodali, Linda Cottler

Wednesday, June 18
2:00 pm - 3:30 pm CT Poster Session 4 (Napoleon Ballroom CD, 3rd Floor)
Alcohol Polysubstance Use among past 30-Day Opioid Users in Northern Florida: A Model for Back Translational Research
Christian Conger, Linda Cottler

📅 Dates: May 21, 2025

🕑 Time: 3:00 pm ET

📍 Location: Online

Learn more here.

📅 Dates: May 29 - May 30, 2025

📍Location: UF Academic and Research Center at Lake Nona, Orlando, FL

Learn more here.

📅 Dates: June 2 - 4, 2025

📍 Location: University of Puget Sound, Tacoma, WA

Learn more here.

📅 Date: Thursday, June 12, 2025

🕑 Time: 12:00 pm ET

📍 Location: Online

Learn more here.

📅 Date: Friday, June 20, 2025

📍 Location: New Orleans

Learn more here.

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If you miss or want to learn more about NDEWS Original Content, you can find our archived content on the NDEWS website:

     • NDEWS Hotspot Alerts using substance-related EMS data
     • NDEWS Rapid Street Reporting (RSR) survey data reports
     • NDEWS Web Monitoring Team Reddit Alerts
     • NDEWS Sentinel Site Reports
     • Previous issues of the NDEWS Weekly Briefings

The Weekly Briefing is a newsletter published each week by the National Drug Early Warning System (NDEWS) Coordinating Center, which is funded by the National Institute on Drug Abuse (U01DA051126) to the University of Florida (MPI: Cottler (contact), Co-Is: Goldberger, Nixon, Striley), New York University (MPI: Palamar), and Florida Atlantic University (Co-I: Barenholtz). Any item may be reproduced provided the source is acknowledged.