Zaleplon overdose

Liskow B, Pikalov A. Zaleplon overdose associated with sleepwalking and complex behaviour. J Am Acad Child Adolesc Psychiatry 2004 43 927-8. 

Drug overdose A case of zaleplon overdose has been described [42 ]. 

The authors concluded that the blue-greenish discoloration of the vomit and urine could be an important sign of zaleplon overdose. 

Louis CL, Fernandez B, Beaumont C, Pinillos MA, Bardom A, Encina Y, Louis CL, Fernandez B, Beaumont C, Pinillos MA, Bardom A, Encina Y. A case of zaleplon overdose. Clin Toxicol 2008 46 782. 

Both zolpidem and zaleplon appear to be nonfatal in overdose. However, overdoses in combination with other central nervous system (CNS) depressant agents pose a greater risk. Recommended treatment consists of general symptomatic and supportive measures, including gastric lavage. Use of flumazenil may be helpful. 

More recently, non-BZD anxiolytics, such as buspirone, and nonbarbiturate, non-BZD hypnotics, such as zolpidem and zaleplon, have been developed. The more recent anxiolytics and hypnotics offer equal efficacy, fewer serious adverse effects, and less risk of a fatal consequence due to accidental or intentional overdose. Unfortunately, these compounds have not entirely eliminated the hazards of tolerance, dependency, and withdrawal syndromes, although they do have a lower abuse potential than their predecessors. 

Zaleplon possesses several of the clinical characteristics of traditional benzodiazepines, including the potential for additive CNS depression when administered with alcohol or other CNS depressants, a low potential for abuse, and relative safety in overdose. Zaleplon exhibited sedative effects similar to those of the benzodiazepines, with a lower likelihood of such undesirable side effects as memory loss, interaction with alcohol, and abuse potential [22],... 

After oral administration zaleplon is well absorbed (71%) and peak concentrations are reached in about 60 minutes. However, it undergoes presystemic elimination and has a systemic availability of about 30%. Its adverse effects include anterograde amnesia, depression, paradoxical reactions (for example restlessness, agitation), dependence, and withdrawal symptoms (related to the dose and duration of treatment). Although the data are limited, it is thought to be relatively safe in overdose, unless it is combined with other CNS depressants. 

The drug class of benzodiazepines includes many compounds that vary widely in po-tenoy, duration of effect, presence or absence of active metabolites, and clinical use (Table 11-14). Two nonbenzodiazepines, zolpidem and zaleplon, have similar 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 or barbiturates. Newer potent, short-acting agents have been considered the sole cause of death in recent forensic cases. 

Flumazenil is a benzodiazepine antagonist used to reverse the effects of benzodiazepines in the treatment of poisoning or in anesthesia [46 , 47, 48, 49 ]. It reduces the risks of complications from drug overdose, obviating the need for invasive interventions such as mechanical ventilation and invasive hemodynamic monitoring [5(E]. However, it is not effective in reversing the amnesic effects of midazolam [51 ]. It has also been used to reverse the effects of zaleplon [52 J, zolpidem [53, 54, 55 ], zopiclone [56", 57" ], antihistamines such as promethazine [58, 59 ], baclofen... 

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