This Week’s Focus: Ketamine
Our focus for this week’s NDEWS Weekly Briefing is on the trends of non-medical use, detection, and the risks associated with overdoses involving ketamine.
We feature our latest NDEWS Special Report that focuses on EMS encounters for nonfatal ketamine-related overdoses in the US, in addition to a NDEWS Web Monitoring Report focusing on ketamine discussion in a rolling two-day window. We also feature our Rapid Street Report from Chicago and include additional studies and articles related to ketamine and novel psychoactive substance use.
NDEWS ORIGINAL CONTENT
NDEWS Special Report: EMS encounters for nonfatal ketamine-related overdoses in the US
Out of 8,793 EMS encounters for nonfatal ketamine-related overdoses from January 1, 2024 to September 30, 2025, 2,076 (23.6%) occurred in Western states, 1,691 (19.3%) in Midwestern states, 4,117 (46.8%) in Southern states and 909 (10.3%) in Northeastern states. The data shows a statistically significant increase in EMS encounters for ketamine-related overdoses across Western, Midwestern, Northeastern and Southern states, and nationally overall. To view the entire Special Report from the weekly briefing, click below.
NDEWS Web Monitoring Report: Ketamine
Due to the large amount of data generated and a use availability restriction, this week’s web monitoring report only shows a two-week period.
Why are we reporting on this?
Recent discussions across monitored substance use subreddits reveal concerning patterns of chronic, high-dose ketamine use alongside reports of potential physical and cognitive health effects. The discussions suggest normalization of heavy ketamine consumption patterns and innovative use contexts that may increase risk.
What is Ketamine?
Ketamine is a dissociative anesthetic that acts primarily as an NMDA receptor antagonist. Originally developed for medical and veterinary use, it produces dissociative effects at sub-anesthetic doses. When used recreationally, the substance can have effects ranging from mild sedation to complete disassociation.
Public Health Impacts:
Reddit discussants report physical and cognitive effects associated with chronic ketamine use patterns. Reddit users describe experiencing symptoms including auditory sensitivity, memory impairment, and difficulty with cognitive tasks following extended use periods. Discussants frequently describe combining ketamine with multiple other substances including MDMA, cocaine, 4-MMC, and poppers. Some commenters report using ketamine as part of unsuccessful attempts to manage mental health conditions before seeking other interventions.
How is it Being Discussed?
Reddit users discuss ketamine across diverse social contexts, from multi-day parties to solo use. Discussants frequently mention ketamine in polydrug contexts, asking about combining it with MDMA or alongside stimulants and other party drugs during extended events. Many commenters interested in using ketamine for the first time are concerned about avoiding full disassociation or “k-holes”. The substance is mentioned both as a recreational drug and as a self-prescribed treatment that some users have tried for serious mental health conditions.
Drug Terms:
Ketamine, K
Rapid Street Report: Substance use in Chicago in the past 12 months, September 12 to 14, 2025
Due to the large amount of data generated and a use availability restriction, this week’s web monitoring report only shows a two-week period.
The Rapid Street Reporting (RSR) team visited Chicago from September 12th to 14th, 2025 and surveyed 237 individuals. After alcohol and marijuana for recreational use, the next most commonly reported substances used in the past 12 months were psilocybin (15.5%), ecstasy/MDMA/Molly (9.2%), marijuana for medical use (7.9%), delta-8 (7.9%) and powder cocaine (7.9%).
Observations from NDEWS Chicago Site Director: Mary Ellen Mackesy-Amiti, PhD
“Results highlight high prevalence of cocaine and other stimulants[…]. In the first half of 2025, over half of overdose deaths involved cocaine, usually in combination with opioids. […] MDMA has appeared in about 1% of drug toxicity deaths[…]. The collected data are consistent with the rising prevalence of psilocybin use noted nationwide[…].”
RECENT PUBLICATIONS
The Lancet Regional Health – Americas
Trends in nonmedical ketamine use, poisonings, related deaths, pharmaceutical diversions, and law enforcement seizures: results from annual population-based repeated cross-sectional studies
A recently published observational study in The Lancet Regional Health – Americas led by NDEWS Co-Director Joseph Palamar examined illicit ketamine datasets from eight unique annual repeated cross-sectional sources. The results indicated that nonmedical ketamine use in the US is rising among adults, while adolescent use continues to decline. Poisonings and pharmaceutical diversions have risen along with law enforcement seizures, which indicates a growling illicit availability.
Toxicology Reports
Rising incidence of recreational ketamine use: Clinical cases and management in emergency settings
A recently published study in Toxicology Reports by Marongui et al. reports a sharp rise in recreational ketamine use in the Netherlands, particularly among young adults in nightlife settings. Adult use doubled from 0.6% in 2018 to 1.2% in 2023, and 25% of nightlife participants aged 16–35 reported use in the past year. This trend coincides with more first aid incidents involving polysubstance use. The authors note that ketamine is absent from standard toxicology screens, and its inclusion could improve diagnostic accuracy and risk management.
Kings college london
Ketamine deaths increase twenty-fold since 2014 with mixing drugs on the rise
A recently published article from King’s College London analyzes the significant increase in ketamine-related deaths across England, Wales, and Northern Ireland since 2014. Coroner’s reports found 696 deaths with the detection of illicit ketamine from 1999 to 2024. The article indicates that even though the rise of illicit ketamine detected post-mortem has risen over the past decade, the proportion of deaths primarily caused by ketamine has fallen due to polydrug use. Opioids, cocaine, benzodiazepines, and gabapentinoids were frequently co-implicated in deaths, with the average number of substances involved in each case also rising.
International Journal of Drug Policy
Novel psychoactive substances in Australian emergency departments: implications for public health practice from multi-centre prospective toxicosurveillance across five states, 2022–2023
A recently published study in the International Journal of Drug Policy by Smith et al. investigates novel psychoactive substances (NPS) detected in emergency department (ED) presentations across five Australian states and 28 EDs between 2022 and 2023. Blood samples from 3,755 ED presentations were analyzed using advanced toxicology screening methods and found at least one NPS across 646 of the presentations. Overall, a total of 1,044 NPS detections were reported l NPS detections were 1,044, with 59 different compounds identified across five effect groups.
Join the UF T32 Training Program in Substance Abuse and Public Health as a Pre or Postdoc! Work with the NDEWS Team!
Are you committed to advancing the science of substance use and public health? The University of Florida’s NIDA-funded T32 Training Program offers predoctoral and postdoctoral scholars an exceptional opportunity to launch impactful research careers focused on NDEWS!
What We Offer:
– Interdisciplinary training at the intersection of addiction science, epidemiology, and surveillance
– Mentorship from leading UF faculty in epidemiology, public health, psychology, medicine, and more
– Hands-on research with landmark and important NIH-funded projects and access to rich data
– Career development support, including grant writing, publishing, and professional networking
– A collaborative, inclusive research community committed to reducing the burden of substance use
Eligibility:
– US citizens or permanent residents
– Interested in a PhD in Epidemiology, or early-stage postdoctoral fellows
– Demonstrated interest in substance use, addiction, or public health research
Location: Gainesville, Florida — a dynamic hub for scientific innovation with high quality of life and low cost of living.
UPCOMING WEBINARS & EVENTS
TIAFT CEC and NPS Committee Joint Webinar: NPS Around the World
📅 Date: October 7, 2025
🕑 Time: 8:00 am – 10:30 pm ET
📍 Location: Online
Adolescent Substance Use – A Deeper Dive: Synthetics, Club Drugs, and New Fads in Substance Misuse
📅 Date: October 8, 2025
🕑 Time: 12:00 pm – 1:00 pm ET
📍 Location: Online
What’s Trending: NPS Discovery Webinar Series – October 2025
📅 Dates: October 9, 2025
🕑 Time: 11:00 am – 12:30 pm ET
📍 Location: Online
2025 American College of Medical Toxicology Psychedelics Seminar
📅 Dates: October 10 & 17, 2025
🕑 Time: 10:00 am – 5:00 pm ET
📍 Location: Online
ABOUT NDEWS
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.
Help Support Our Work!
You can share the NDEWS Weekly Briefing with friends, colleagues, and others who would benefit from information on recent and relevant news, articles, and data related to novel drug trends in the US and globally by clicking here.
Get in Touch with NDEWS
Share your research, news, and events through our submission form.
Share your comments on our newsletter through our feedback form.
For more information on NDEWS’ efforts, visit our website.
Follow NDEWS on Twitter/X: @NDEWSnews
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), NYU Langone Health (MPI: Palamar), and Florida Atlantic University (Co-I: Barenholtz). Any item may be reproduced provided the source is acknowledged.