The Z-drugs (zolpidem, zopiclone, and zaleplon), as the innovative hypnotics, have an improvement over the traditional benzodiazepines in the management of insomnia. Z-drugs have significant hypnotic effects by reducing sleep latency and improving sleep quality, though duration of sleep may not be significantly increased. As benzodiazepines, Z-drugs exert their effects through increasing the transmission of γ-aminobutyric acid. Z-drugs overdose are less likely to be fatal, more likely would result in poisoning. Z-drugs can be detected in blood, urine, saliva, and other postmortem specimens through liquid chromatography-mass spectrometry techniques. Zolpidem and zaleplon exhibit significant postmortem redistribution. Z-drugs have improved pharmacokinetic profiles, but incidence of neuropsychiatric sequelae, poisoning, and death may prove to be similar to the other hypnotics. This review focuses on the pharmacology and toxicology of Z-drugs with respect to their adverse effect profile and toxicity and toxicology data in the field of forensic medicine.
Acetamides/poisoning* ; Azabicyclo Compounds/poisoning* ; Drug Overdose ; Forensic Medicine/trends* ; Forensic Toxicology/trends* ; Humans ; Hypnotics and Sedatives/poisoning* ; Piperazines/poisoning* ; Pyridines/poisoning* ; Pyrimidines/poisoning* ; Sleep Initiation and Maintenance Disorders/drug therapy* ; Zolpidem

A 63-year-old man was found in the street after overrun by a car. Postmortem CT revealed multiple bone fractures, but surprisingly all without any relevant hemorrhage which would have been expected under such circumstances. A round radiopaque formation was found in the duodenum, which was reminiscent of ingested tablets. The toxicological analysis revealed high concentrations of zopiclone and alcohol. By combining radiologic and forensic results, zopiclone and alcohol intoxication were concluded as the cause of death, followed by a postmortem overrun accident.
Accidents, Traffic ; Alcoholic Intoxication/*diagnosis ; Azabicyclo Compounds/analysis/*poisoning ; Duodenum/*radiography ; Fatal Outcome ; Humans ; Hypnotics and Sedatives/analysis/*poisoning ; Male ; Middle Aged ; Piperazines/analysis/*poisoning ; Tomography, X-Ray Computed/*methods