Poisoning benzodiazepines

Gaudreault P, Guay J, Thivierge RL, Verdy I. Benzodiazepine poisoning. Clinical and pharmacological considerations and treatment. Drug Saf 1991 6(4) 247-65. 

For cyanide and cyanogen, antidote should be administered as soon as possible. The Lilly Cyanide Antidote Kit contains amyl nitrite, sodium nitrite, and sodium thiosulfate. Cobalt edentate or 4-dimethylaminophenol are alternative antidotes for cyanide poisoning. Benzodiazepines or barbiturates may be required to control severe seizures. 

The consequences of benzodiazepine use in the elderly may be severe. Benzodiazepines are common in drug poisoning suicides in the elderly (Carlsten et al. 2003). This is especially apparent for the hypnotics flunitrazepam and nitrazepam. Benzodiazepines are also associated with an increased risk of motor vehicle crashes in the elderly (Hebert et al. 2007). 

The benzodiazepines such as diazepam, oxazepam, and temazepam are common causes of acute poisoning, but rarely cause serious toxicity by themselves, even in enormous doses. They can potentiate central nervous system depression from other drugs, including alcohol. 

The principal disadvantages of barbiturates as hypnotics include the development of physical dependence, a relatively low therapeutic index (and the potential of poisoning, as in suicide), suppression of REM sleep, and possible hangover effects. As mentioned above, benzodiazepines (e.g., flurazepam or brotizolam) are hypnotics as effective as barbiturates and are much safer in terms of their therapeutic index, addiction potential, and REM sleep-deprivation effects. Thus benzodiazepines have displaced barbiturates as sedative hypnotics. 

Common adverse psychologic consequences of hallucinogenic drugs include panic reactions ("bad trips") and acute psychotic reactions with PCP. Treatment includes benzodiazepines for sedation and constant monitoring by a nondrugged companion for several hours. Acidification of the urine (see Chapter 59 Management of the Poisoned Patient) may hasten PCP excretion. 

Diflunisal Overdose (15 g) of diflunisal leads to poisoning, which could be fatal.51 Treatment can be given by gastric lavage and supportive care. Interactions of diflunisal with indomethacin, paracetamol, antacids, benzodiazepines, and probenecid have been reported.5 Concomitant use with indomethacin should be avoided, as this could cause fatal GI complications. 

Serfaty, M., Masterton, G. (1993). Fatal poisonings attributed to benzodiazepines in Britain during the 1980s. British Journal of Psychiatry, 163, 386—393. 

Flumazenil is used as a benzodiazepine antagonist in the treatment of poisoning or the reversal of benzodiazepine effects in anesthesia 1,2) or in neonates (3). Guidelines for its use have been summarized (4). The problems in its use are those of dose adjustment, the risks of panic anxiety, seizures, or other signs of excessively rapid benzodiazepine withdrawal, and pharmacokinetic problems due to the short half-life of flumazenil (about 1 hour) compared with the longer half-lives of most benzodiazepines (5). Its use is also commonly associated with vomiting and headache, and rarely with psychosis or sudden cardiac death (SEDA-17,... 

The initial clinical review should include a search for known consequences of poisoning, which include impaired consciousness with flacddity (benzodiazepines, alcohol, trichloroethanol) or with hypertonia (tricyclic antidepressants, antimuscaiinic agents), hypotension, shock, cardiac arrhythmia, evidence of convulsions, behavioural disturbances (psychotropic drugs), hypothermia, aspiration pneumonia and cutaneous blisters, burns in the mouth (corrosives). 

Verstraete AG, Buylaert WA, and Blondeel L (1998) Use of benzodiazepines in the general population and their involvement in acute self-poisoning cases. Pharmacoepidemiology and Drug Safety. 7(6) 403—410. 

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