Opioid overdoses following use of cocaine and methamphetamine in New South Wales, and the public health responses

Peter Chisholm; Jared Brown; Thanjira Jiranantakan; Mary Ellen Harrod; Catherine McDonald; Una Cullinan; Darren M Roberts

doi:10.1111/1742-6723.70038

Opioid overdoses following use of cocaine and methamphetamine in New South Wales, and the public health responses

Emerg Med Australas. 2025 Apr;37(2):e70038. doi: 10.1111/1742-6723.70038.

Authors

Peter Chisholm^{1

2

3}, Jared Brown^{1

2

4}, Thanjira Jiranantakan^{1

2

4

5}, Mary Ellen Harrod⁶, Catherine McDonald⁷, Una Cullinan⁸, Darren M Roberts^{2

3

5}

Affiliations

¹ Centre for Alcohol and Other Drugs, New South Wales Ministry of Health, Sydney, New South Wales, Australia.
² New South Wales Poisons Information Centre, Sydney Children's Hospitals Network, Sydney, New South Wales, Australia.
³ Faculty of Medicine and Health, University of New South Wales, Sydney, New South Wales, Australia.
⁴ Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia.
⁵ Edith Collins Centre, Drug Health Services, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia.
⁶ NSW Users and AIDS Association, Sydney, New South Wales, Australia.
⁷ NSW Health Pathology, Forensic & Analytical Science Service, Forensic Toxicology Laboratory, Lidcombe, New South Wales, Australia.
⁸ NSW Health Pathology, Forensic & Analytical Science Service, Illicit Drug Analysis Unit, Lidcombe, New South Wales, Australia.

Abstract

Objective: Recent years have seen sporadic reports in Australia of stimulants being contaminated with opioids. Since late 2023, there has been an increase in opioid overdoses among individuals in New South Wales (NSW) using substances believed to be cocaine or methamphetamine. We analysed the frequency and characteristics of these cases and describe our public health responses.

Methods: The Prescription, Recreational & Illicit Substance Evaluation (PRISE), operated by NSW health since July 2018, is a statewide surveillance, epidemiology, and toxicity response programme. We did a retrospective analysis of each case of opioid toxicity following use of cocaine or methamphetamine submitted to the PRISE programme from January 2022 to June 2024, categorising cases into confirmed, probable, and suspected.

Results: Thirty-four cases were found, 19 involving cocaine and 15 involving methamphetamine. Twenty-two (65%) were classified as confirmed, and 12 (35%) as probable. There were two deaths (6%). Twenty-three cases (68%) were in Sydney. Multiple stakeholders reviewed trends and formulated public health responses, leading to the distribution of public drug warnings and media releases in November 2023 and February 2024 because of ongoing case detections.

Conclusions: The increase in detections, which continued in the months following the public health responses, underscores the need for comprehensive surveillance, response, monitoring, and reporting of this phenomenon in NSW. Engagement with clinicians and the community is essential for the success of this programme.

Keywords: drug contamination; drug epidemiology; drug substitution; drug surveillance; opioid overdose.

MeSH terms

Adolescent
Adult
Aged
Cocaine* / adverse effects
Female
Humans
Male
Methamphetamine* / adverse effects
Middle Aged
New South Wales / epidemiology
Opiate Overdose* / epidemiology
Public Health* / methods
Retrospective Studies

Substances

Methamphetamine
Cocaine