The drug class of benzodiazepines includes many compounds that vary widely in potency, duration of effect, presence or absence of active metabolites, and clinical use (Table II–14). Three nonbenzodiazepines—eszopiclone, zaleplon, and zolpidem—have similar clinical effects and are included here. In general, death from benzodiazepine overdose is rare unless the drugs are combined with other CNS-depressant agents, such as ethanol, opioids, and barbiturates. Newer potent, short-acting agents have been considered the sole cause of death in recent forensic cases.