VIENNA, Austria – 4 March 2025: Etomidate is a short-acting intravenous general anaesthetic.[i] Over the past few years, multiple countries across the globe have reported detections of etomidate in illicit drug samples and toxicology cases, suggesting the use of the substance for non-medical purposes. Moreover, several etomidate analogues have been identified in some East and South-East Asian countries (including metomidate, isopropoxate, propoxate, sec-butomidate, butomidate, CF3-etomidate and 4F-etomidate), especially after introducing national regulations[1] to address the non-medical use of etomidate.
E-liquids containing etomidate are being found in East and South-East Asia and Oceania. In the United Kingdom, etomidate has been detected in samples submitted to a drug checking service in tablet and crystalline forms.[ii]
Etomidate and analogues have been most notably detected on illicit drug markets in East and South-East Asia in recent years. In China, etomidate was identified in e-liquids after the class scheduling of synthetic cannabinoids in 2021. After controlling etomidate in October 2023, other etomidate analogues have been identified in China as for example metomidate, isopropoxate and propoxate, which were subsequently controlled in July 2024.[iii]
Following the emergence of etomidate in e-cigarettes in mainland China, Hong Kong, China, reported its first cases of etomidate misuse at the end of 2023. Additionally, since January 2024, the country has seen a rise in detections of the analogues propoxate/isopropoxate.[iv]
In 2025, the Customs and Excise Department has reported on multiple ongoing investigations related to seizures suspected to involve etomidate (commonly referred to “space oil” in Hong Kong, China).[v]
Moreover, in January 2025, an e-vaporiser distribution network suspected to be related to etomidate was uncovered in Singapore (also known under the street name kpod).[vi] Illicit etomidate was also found in drug samples in Cambodia, Macao, China, Indonesia and Malaysia.[vii]
There are indications that etomidate might also be illegally produced rather than diverted from legal sources in the region. For instance, in December 2024, the Office of the Narcotics Control Board in Thailand reported on a seizure of 2,200 litres and 250 kilograms of chemicals as well as equipment in a warehouse in Bangkok that could have been used for the production of 200 kilograms of illicit etomidate.[viii]
Photo: E-liquid samples with etomidate detected in Thailand
Credit: Thailand, Office of the Narcotics Control Board.
The non-medical use of etomidate seems to have spread further to other regions such as North America, Europe and Oceania. In Canada, etomidate has been flagged as a substance of interest after several detections in drug samples and via web monitoring since early 2023.[ix] In the United States, a health update was released in August 2024 after detecting illicit etomidate in Philadelphia’s drug supply. Etomidate was co-detected with fentanyl and medetomidine.[x]
In Europe, a United Kingdom drug checking service identified etomidate in nine drug samples since 2023. The substance was co-detected with protonitazene, protonitazepyne and diazepam in some samples. For more than half of the samples, users intended to purchase oxycodone tablets.[xi]
Similar to the East and Southeast Asian region, in New Zealand, drug checking services have recently identified etomidate in vapes.[xii]
The increasing detections on illicit drug markets of etomidate and its analogues calls for preparedness among health care providers. In addition, drug testing and toxicology laboratories need to maintain up-to-date methods and consider routine screening processes to effectively identify etomidate and its analogues. Given the rapid spread of these substances, increased awareness and monitoring of early warning systems is crucial.
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[1] For instance, in China etomidate was controlled in October 2023 (see China Drug Situation Report 2023 here). In Singapore, etomidate is classified as a poison under the Poisons Act (see endnote vi) and in Hong Kong, China, etomidate and three analogues (metomidate, propoxate, and isopropoxate) are listed as dangerous drugs as of 14 February 2025 (see Hong Kong, China Cap. 134 Dangerous Drugs Ordinance here).
Endnotes:
[i] Williams L.M., Boyd K.L. and Fitzgerald B.M., “Etomidate”, National Library of Medicine, 26 June 2023. Available at: Etomidate - StatPearls - NCBI Bookshelf (accessed on 27 February 2025).
[ii] WEDINOS, “Sample results”, drug checking sample database. Available at: https://www.wedinos.org/sample-results (accessed on 26 February 2025).
[iii] United Nations, Office on Drugs and Crime (UNODC), “Emerging drug-related challenges in East and Southeast Asia: October 2024”, newsletter, 31 October 2024.
[iv] Yee-Ting Cheung, Chun-Wing Yeung, Kelvin Yat-Chung Yu, Choi- Yee Lau, Hok-Fung Tong and Yeow-Kuan Chong, “A recent increasing occurrence of etomidate and propoxate/isopropoxate misuse”, Clinical Toxicology, vol. 63, No. 1 (January 2025), pp. 65-67.
[v] See press releases related to etomidate at: Hong Kong, China, Customs and Excise Department, Customs Announcement. Available at: Hong Kong Customs and Excise Department - Search Result (accessed on 27 February 2025).
[vi] Singapore, Health Sciences Authority, Immigration and Checkpoints Authority and Police Force, E-vaporisers, duty-unpaid cigarettes and illicit substances found in industrial unit, press release, 24 January 2025.
[vii] UNODC, “Emerging drug-related challenges in East and Southeast Asia: January 2025”, newsletter, 30 January 2025 and UNODC, responses to the annual report questionnaire.
[viii] United Nations, Office on Drugs and Crime, “Emerging drug-related challenges in East and Southeast Asia: January 2025”, newsletter, 30 January 2025.
[ix] Canada, “Canadian Drug and Substance Watch”, early warning system. Available at: New and emerging substances: Canadian Drug and Substance Watch — Canada.ca (accessed on 4 March 2025).
[x] United States, Philadelphia Department of Public Health, Etomidate detected in Philadelphia’s drug supply and involved in overdose deaths, health update, 12 August 2024.
[xi] WEDINOS, “Sample results”, drug checking sample database. Available at: https://www.wedinos.org/sample-results (accessed on 26 February 2025).
[xii] High Alert, Space oils and kpods – what’s going on with etomidate in vapes?, alert 5 February 2025. Available at: https://highalert.org.nz/articles/space-oil-and-kpods-whats-going-on-with-etomidate-in-vapes/ (accessed on 4 March 2025).