BACKGROUND AND AIMS: Gamma-hydroxybutyrate (GHB) is an endogenous neurochemical and illicit synthetic drug. Its precursors, gamma-butyrolactone (GBL) and 1,4-butanediol (1,4-BD), are often used as substitutes. We aimed to describe GHB-related harms in New South Wales (NSW), Australia.

DESIGN, SETTING AND CASES: Descriptive epidemiological study of data from three administrative datasets: emergency department (ED) presentations from 88 hospitals (1 July 2015 to 31 January 2024 - the latest available), admitted patient data from all NSW hospitals (1 July 2015 to 30 June 2023) and a subset of NSW Police Force seizure data. Note: analysis was not undertaken, data are presented descriptively.

MEASUREMENTS: ED presentations and hospitalisations were analysed for GHB-related presentations and admissions including severity of presentation, intubation and intensive care. NSW Police Force seizure data were examined for all analytically confirmed samples of GHB, GBL and 1,4-BD to assess trends over time.

FINDINGS: Over the study period, there were 9612 GHB-related ED presentations. Between July 2023 and January 2024, this was 101 per 100 000 unplanned presentations, relative to the previous full-year peak of 73.7 per 100 000 in 2022-2023 and the 2015-2016 rate of 24.9 per 100 000. The majority (56.1%) were assessed as Australian Triage Category 1 or 2, indicating the highest level of need. ED presentations in regional or remote areas accounted for 13.8% of all presentations in the most recent data, relative to 3.4% at the start of the study period. Hospitalisations totalled 6420 episodes, peaking at 19.6 per 100 000 population in 2020-2021. Nearly one in five patients required intubation, and a similar proportion required admission to intensive care. There was a trend of women accounting for a larger proportion of ED presentations and hospitalisations over time. GHB accounted for 0.1% of all police seizures analysed, and showed a shift from GBL to 1,4-BD dominance from 2022 onwards.

CONCLUSIONS: Gamma-hydroxybutyrate-related emergency department presentations and hospitalisations in New South Wales, Australia, appear to have increased over the period from 2015 to 2024, which can support public health campaigns to reduce gamma-hydroxybutyrate-related harms.