New biomarker detects GHB up to 72 hours after ingestion, Zurich researchers reveal
Researchers from the University of Zurich have identified a biomarker that extends the detection window for GHB, the "date rape drug", to 72 hours. The method has already been tested on more than 2,400 real forensic samples.
Biomarker extends GHB detection to 72 hours in urine
Researchers at the University of Zurich have discovered a new biomarker capable of identifying the presence of GHB — known as the "date rape drug" — in urine up to 72 hours after ingestion, according to Observador. The discovery significantly extends the detection window for this substance, which disappears within a few hours using conventional methods.
"The usual detection period is approximately six hours in blood and 12 hours in urine," explains the team from the Institute of Forensic Medicine at the University of Zurich in a press statement.
Compound identified in 2021 now validated in real cases
The biomarker in question — called GHB-pentose — results from the combination of gamma-hydroxybutyrate (GHB) with sugar and was first identified by the same team in 2021. "Unlike GHB itself, this biomarker remains detectable in urine for a longer period after ingestion," the statement says.
In a study published on Tuesday, the researchers analysed 2,414 anonymised urine samples collected between 2024 and 2026 as part of real forensic cases. Of these samples, 14 proved "particularly useful": the levels of GHB measured were below the detection threshold for standard methods, but GHB-pentose remained identifiable.
"In eight of these 14 cases, details in the files corroborated the suspicion that GHB had been consumed or administered previously," the researchers explained. Three of these cases involved alleged crimes — two thefts and an alleged rape — with the urine samples having been collected only between 13 and 16 hours after the alleged incidents.
Substance difficult to detect by victims and analysts
The Swiss Ministry of Health classifies GHB as one of the "ideal candidates" for malicious use in the context of crimes: the substance is "virtually odourless", miscible in water and practically imperceptible in a drink. The euphoric effect manifests itself after only 15 minutes and develops into a state of deep fatigue.
Upon waking, victims generally have no memory of what happened, the ministry adds. The new method establishes that GHB-pentose can indicate previous consumption of GHB even when the substance is no longer detectable by conventional analytical processes.
Source: Observador