Forensic interpretation of zolpidem in South Korea (2022-2024): Postmortem specimen analysis and drug-facilitated crimes.

Zolpidem, a non-benzodiazepine hypnotic, is one of the most widely prescribed sleep aids in South Korea and is frequently implicated in forensic toxicology. A retrospective analysis was conducted on zolpidem-positive autopsy cases (N = 1583) investigated by the National Forensic Service between 2022 and 2024. The manner and cause of death were classified, and zolpidem concentrations were measured in three biological matrices: peripheral blood (PB), cardiac blood (HB), and liver. Zolpidem analysis was performed using gas chromatography-mass spectrometry (GC/MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) following solid-phase extraction (SPE). Among zolpidem-positive autopsies, suicide accounted for 43.1% (n = 676), with drug poisoning representing the dominant method (72.8% of suicides). In drug-related suicide cases (n = 251), zolpidem was the sole detected agent in 15.1%, while the majority (84.9%) involved poly-drug exposure. A wide range of non-pharmaceutical toxicants-including carbon monoxide, agrochemicals, chemical substances such as gases, nitrite, ethylene glycol, cyanide, and other miscellaneous agents-were also co-detected. Zolpidem was also the most frequently detected drug in driving under the influence of drugs (DUID) cases (30.0%) and drug-facilitated sexual assault (DFSA) submissions (5.1%) during the study period, highlighting its role in both fatal and nonfatal forensic toxicology. These findings emphasize the importance of appropriate clinical use, matrix- and context-specific toxicological assessment, and strengthened public health strategies to address the potential risks associated with zolpidem use.