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'''Benzodiazepine overdose''' describes the ingestion of one of the drugs in the [[benzodiazepine]] class in quantities greater than are recommended or generally practiced. Death as a result of benzodiazepines is uncommon but does occasionally happen.<ref>{{Cite book|last1=Dart |first1=Richard C. |title=Medical Toxicology |url=http://books.google.com/?id=qDf3AO8nILoC |edition=3rd |date=1 December 2003 |publisher=Lippincott Williams & Wilkins |location=USA |isbn=978-0781728454 |pages=811}}</ref> Deaths after hospital admission are considered to be low.<ref>{{Cite journal|author=Höjer J, Baehrendtz S, Gustafsson L |title=Benzodiazepine poisoning: experience of 702 admissions to an intensive care unit during a 14-year period |journal=J. Intern. Med. |volume=226 |issue=2 |pages=117–22 |year=1989 |month=August |pmid=2769176}}</ref> However, combinations of high doses of benzodiazepines with [[Ethanol|alcohol]], [[barbiturates]], [[opioids]] or [[tricyclic antidepressants]] are particularly dangerous, and may lead to severe complications such as [[coma]] or death. The most common symptoms of overdose include [[central nervous system]] (CNS) depression and intoxication with impaired balance, [[ataxia]], and slurred speech. Severe symptoms include [[coma]] and [[respiratory depression]]. Supportive care is the mainstay of treatment of benzodiazepine overdose. There is an antidote, [[flumazenil]], but its use is controversial.<ref name="Seger"/>
'''Benzodiazepine overdose''' describes the ingestion of one of the drugs in the [[benzodiazepine]] class in quantities greater than are recommended or generally practiced. Death as a result of benzodiazepines is uncommon but does occasionally happen.<ref>{{Cite book|last1=Dart |first1=Richard C. |title=Medical Toxicology |url=http://books.google.com/?id=qDf3AO8nILoC |edition=3rd |date=1 December 2003 |publisher=Lippincott Williams & Wilkins |location=USA |isbn=978-0781728454 |pages=811}}</ref> Deaths after hospital admission are considered to be low.<ref>{{Cite journal|author=Höjer J, Baehrendtz S, Gustafsson L |title=Benzodiazepine poisoning: experience of 702 admissions to an intensive care unit during a 14-year period |journal=J. Intern. Med. |volume=226 |issue=2 |pages=117–22 |year=1989 |month=August |pmid=2769176}}</ref> However, combinations of high doses of benzodiazepines with [[Ethanol|alcohol]], [[barbiturates]], [[opioids]] or [[tricyclic antidepressants]] are particularly dangerous, and may lead to severe complications such as [[coma]] or death. The most common symptoms of overdose include [[central nervous system]] (CNS) depression and intoxication with impaired balance, [[ataxia]], and slurred speech. Severe symptoms include [[coma]] and [[respiratory depression]]. Supportive care is the mainstay of treatment of benzodiazepine overdose. There is an antidote, [[flumazenil]], but its use is controversial.<ref name="Seger"/>


As benzodiazepines are one of the most highly prescribed class of drugs<ref>{{Cite journal|doi=10.1192/bjp.173.5.433 |author=Taylor S, McCracken CF, Wilson KC, Copeland JR |title=Extent and appropriateness of benzodiazepine use. Results from an elderly urban community |journal=Br J Psychiatry |volume=173 |issue= 5|pages=433–8 |year=1998 |month=November |pmid=9926062}}</ref> they are commonly used in self-poisoning by [[drug overdose]].<ref name="Ngo AS, Anthony CR, Samuel M, Wong E, Ponampalam R 2007 27–37">{{Cite journal|author=Ngo AS, Anthony CR, Samuel M, Wong E, Ponampalam R |title=Should a benzodiazepine antagonist be used in unconscious patients presenting to the emergency department? |journal=Resuscitation |volume=74 |issue=1 |pages=27–37 |year=2007 |month=July |pmid=17306436 |doi=10.1016/j.resuscitation.2006.11.010}}</ref><ref>{{Cite journal|author=Jonasson B, Jonasson U, Saldeen T |title=Among fatal poisonings dextropropoxyphene predominates in younger people, antidepressants in the middle aged and sedatives in the elderly |journal=J. Forensic Sci. |volume=45 |issue=1 |pages=7–10 |year=2000 |month=January |pmid=10641912}}</ref> The various benzodiazepines differ in their toxicity since they produce varying levels of sedation, with [[oxazepam]] being least toxic and least sedative and [[temazepam]] the most toxic and most sedative.<ref>[http://www.bmj.com/content/310/6974/219.full Relative toxicity of benzodiazepines in overdose]</ref> [[Temazepam]] is more frequently involved in drug-related deaths causing more deaths per million prescriptions than all other benzodiazepines. A 1993 British study found temazepam to have the highest number of deaths per million prescriptions among medications commonly prescribed in the 1980s. Temazepam's rate of 11.9 (95% confidence interval 10.9-12.8 range) trumped all other benzodiazepines; a rate which is above that of some [[tricyclic antidepressants]] and approximately equal to that of some [[barbiturates]]. In contrast, [[oxazepam]] had a rate of 2.3 (1.2-3.4 range), and the rate for all benzodiazepines combined was 5.7 - all taken with or without alcohol, although temazepam was far more likely to cause death as a single agent without the mixture of other CNS depressants relative to other benzodiazepines.<ref>{{cite journal |author=Serfaty M, Masterton G |title=Fatal poisonings attributed to benzodiazepines in Britain during the 1980s |journal=Br J Psychiatry |volume=163 |issue= 3|pages=386–93 |year=1993 |pmid=8104653 |doi=10.1192/bjp.163.3.386}}</ref> Since that 1993 British study, numerous other studies conducted in the United Kingdom, Ireland, Canada, Sweden, Norway, and two in Australia comparing the relative toxicities of benzodiazepines have corroborated the 1993 British study findings that temazepam was by far the most toxic benzodiazepine.<ref>Buckley NA, Dawson AH, Whyte IM, McManus P, Ferguson N.Correlations between prescriptions and drugs taken in self-poisoning: Implications for prescribers and drug regulation.Med J Aust (in press)</ref><ref name="pmid12474705">{{cite journal |author=Buckley NA, Dawson AH, Whyte IM, O'Connell DL. |title=[Relative toxicity of benzodiazepines in overdose.] |journal=BMJ |volume=310 |issue= 6974|pages=219–21 |year=1995 |pmid=7866122 |doi= |url=http://www.bmj.com/cgi/content/full/310/6974/219 |pmc=2548618}}</ref>
As benzodiazepines are one of the most highly prescribed class of drugs<ref>{{Cite journal|doi=10.1192/bjp.173.5.433 |author=Taylor S, McCracken CF, Wilson KC, Copeland JR |title=Extent and appropriateness of benzodiazepine use. Results from an elderly urban community |journal=Br J Psychiatry |volume=173 |issue= 5|pages=433–8 |year=1998 |month=November |pmid=9926062}}</ref> they are commonly used in self-poisoning by [[drug overdose]].<ref name="Ngo AS, Anthony CR, Samuel M, Wong E, Ponampalam R 2007 27–37">{{Cite journal|author=Ngo AS, Anthony CR, Samuel M, Wong E, Ponampalam R |title=Should a benzodiazepine antagonist be used in unconscious patients presenting to the emergency department? |journal=Resuscitation |volume=74 |issue=1 |pages=27–37 |year=2007 |month=July |pmid=17306436 |doi=10.1016/j.resuscitation.2006.11.010}}</ref><ref>{{Cite journal|author=Jonasson B, Jonasson U, Saldeen T |title=Among fatal poisonings dextropropoxyphene predominates in younger people, antidepressants in the middle aged and sedatives in the elderly |journal=J. Forensic Sci. |volume=45 |issue=1 |pages=7–10 |year=2000 |month=January |pmid=10641912}}</ref> The various benzodiazepines differ in their toxicity since they produce varying levels of sedation, with [[oxazepam]] being least toxic and least sedative and [[temazepam]] the most toxic and most sedative.<ref>[http://www.bmj.com/content/310/6974/219.full Relative toxicity of benzodiazepines in overdose]</ref> [[Temazepam]] is more frequently involved in drug-related deaths causing more deaths per million prescriptions than all other benzodiazepines. A 1993 British study found temazepam to have the highest number of deaths per million prescriptions among medications commonly prescribed in the 1980s. Temazepam's rate of 11.9 (95% confidence interval 10.9-12.8 range) trumped all other benzodiazepines; a rate which is above that of some [[tricyclic antidepressants]] and approximately equal to that of some [[barbiturates]]. In contrast, [[oxazepam]] had a rate of 2.3 (1.2-3.4 range), and the rate for all benzodiazepines combined was 5.7 - all taken with or without alcohol, although temazepam was far more likely to cause death as a single agent without the mixture of other CNS depressants relative to other benzodiazepines.<ref>{{cite journal |author=Serfaty M, Masterton G |title=Fatal poisonings attributed to benzodiazepines in Britain during the 1980s |journal=Br J Psychiatry |volume=163 |issue= 3|pages=386–93 |year=1993 |pmid=8104653 |doi=10.1192/bjp.163.3.386}}</ref> Since that 1993 British study, numerous other studies conducted in the United Kingdom, Ireland, Canada, Sweden, Norway, and two in Australia comparing the relative toxicities of benzodiazepines have corroborated the 1993 British study findings that temazepam was by far the most toxic benzodiazepine.<ref>Buckley NA, Dawson AH, Whyte IM, McManus P, Ferguson N.Correlations between prescriptions and drugs taken in self-poisoning: Implications for prescribers and drug regulation.Med J Aust (in press)</ref><ref name="pmid12474705">{{cite journal |author=Buckley NA, Dawson AH, Whyte IM, O'Connell DL. |title=[Relative toxicity of benzodiazepines in overdose.] |journal=BMJ |volume=310 |issue= 6974|pages=219–21 |year=1995 |pmid=7866122 |doi= |url=http://www.bmj.com/cgi/content/full/310/6974/219 |pmc=2548618}}</ref>


==Toxicity==
==Toxicity==

Revision as of 15:53, 5 April 2011

Benzodiazepine overdose
SpecialtyEmergency medicine Edit this on Wikidata

Benzodiazepine overdose describes the ingestion of one of the drugs in the benzodiazepine class in quantities greater than are recommended or generally practiced. Death as a result of benzodiazepines is uncommon but does occasionally happen.[1] Deaths after hospital admission are considered to be low.[2] However, combinations of high doses of benzodiazepines with alcohol, barbiturates, opioids or tricyclic antidepressants are particularly dangerous, and may lead to severe complications such as coma or death. The most common symptoms of overdose include central nervous system (CNS) depression and intoxication with impaired balance, ataxia, and slurred speech. Severe symptoms include coma and respiratory depression. Supportive care is the mainstay of treatment of benzodiazepine overdose. There is an antidote, flumazenil, but its use is controversial.[3]

As benzodiazepines are one of the most highly prescribed class of drugs[4] they are commonly used in self-poisoning by drug overdose.[5][6] The various benzodiazepines differ in their toxicity since they produce varying levels of sedation, with oxazepam being least toxic and least sedative and temazepam the most toxic and most sedative.[7] Temazepam is more frequently involved in drug-related deaths causing more deaths per million prescriptions than all other benzodiazepines. A 1993 British study found temazepam to have the highest number of deaths per million prescriptions among medications commonly prescribed in the 1980s. Temazepam's rate of 11.9 (95% confidence interval 10.9-12.8 range) trumped all other benzodiazepines; a rate which is above that of some tricyclic antidepressants and approximately equal to that of some barbiturates. In contrast, oxazepam had a rate of 2.3 (1.2-3.4 range), alprazolam had a rate of 5.9 (4.8-6.9 range), diazepam 4.0 (2.4-5.6 range), lorazepam 6.6 (5.7-7.5 range), nitrazepam 7.6 (6.4-8.8 range), and flunitrazepam 8.3 (7.4-9.1 range). In addition to the aforementioned benzodiazepines and their fatal toxicity index, there were more in the study including clonazepam, triazolam, flurazepam, chlordiazepoxide, and bromazepam. The rate for all benzodiazepines combined as a whole group was 5.7 - all taken with or without alcohol, although temazepam was far more likely to cause death as a single agent without the mixture of other CNS depressants relative to other benzodiazepines.[8] Since that 1993 British study, numerous other studies conducted in the United Kingdom, Ireland, Canada, Sweden, Norway, and two in Australia comparing the relative toxicities of benzodiazepines have corroborated the 1993 British study findings that temazepam was by far the most toxic benzodiazepine.[9][10]

Toxicity

Benzodiazepines have a wide therapeutic index and taken alone in overdose rarely cause severe complications or fatalities.[11][12] They are, however, not devoid of serious toxicity and cases of severe coma or fatality have been reported.[13] This is especially true of temazepam, which has a far greater fatal toxicity index compared to all other benzodiazepines. Temazepam has been well documented to have caused overdose alone without being mixed with ethanol or any other CNS depressant.[14] Taken in overdose in combination with alcohol, barbiturates, opioids, tricyclic antidepressants, or sedating antipsychotics, anticonvulsants, or antihistamines are particularly dangerous.[15] In the case of alcohol and barbiturates not only do they have an additive effect, they also increase the binding affinity of benzodiazepines to the benzodiazepine binding site which results in a very significant potentiation of the CNS and respiratory depressant effects.[16][17][18][19][20] Additionally, the elderly and those with chronic illnesses are much more vulnerable to lethal overdose with benzodiazepines. Fatal overdoses can occur at relatively low doses in these individuals.[11][13][21][22]

Signs and symptoms

Following an acute overdose of a benzodiazepine the onset of symptoms is typically rapid with most developing symptoms within 4 hours.[23] Patients initially present with mild to moderate impairment of central nervous system function. Initial signs and symptoms include intoxication, somnolence, diplopia, impaired balance, impaired motor function, anterograde amnesia, ataxia, and slurred speech. Most patients with pure benzodiazepine overdose will usually only exhibit these mild CNS symptoms.[11][23] Paradoxical reactions such as anxiety, delirium, combativeness, hallucinations, and aggression can also occur following benzodiazepine overdose.[24] Gastrointestinal symptoms such as nausea and vomiting have also been occasionally reported.[11]

Cases of severe overdose have been reported and symptoms displayed may include prolonged deep coma or deep cyclic coma, apnea, respiratory depression, hypoxemia, hypothermia, hypotension, bradycardia, cardiac arrest, and pulmonary aspiration, with the possibility of death.[23][25][26][27][28][29] Severe consequences are rare following overdose of benzodiazepines alone but the severity of overdose is increased significantly if benzodiazepines are taken in overdose in combination with other medications.[29] Significant toxicity may result following recreation drug misuse in conjunction with other CNS depressants such as opioids or ethanol.[30][31][32][33] The duration of symptoms following overdose is usually between 12 and 36 hours in the majority of cases.[11] The majority of drug-related deaths involve misuse of heroin or other opioids in combination with benzodiazepines or other CNS depressant drugs. In most cases of fatal overdose it is likely that lack of opioid tolerance combined with the depressant effects of benzodiazepines is the cause of death.[34]

The symptoms of an overdose such as sleepiness, agitation and ataxia occur much more frequently and severely in children. Hypotonia may also occur in severe cases.[35]

Pathophysiology

Benzodiazepines act by enhancing the effect of the neurotransmitter gamma-aminobutyric acid (GABA), they act by binding to a specific benzodiazepine receptor causing CNS depression. In overdose situations this pharmacological effect is extended leading to a more severe CNS depression and potentially coma.[11] Benzodiazepine overdose related coma may be characterised by an alpha pattern with the central somatosensory conduction time (CCT) after median nerve stimulation being prolonged and the N20 to be dispersed. Brain-stem auditory evoked potentials demonstrate delayed interpeak latencies (IPLs) I-III, III-V and I-V. Toxic overdoses therefore of benzodiazepines cause prolonged CCT and IPLs.[36][37][38]

Diagnosis

The diagnosis of benzodiazepine overdose may be difficult, but is usually made based on the clinical presentation of the patient along with a history of overdose.[11][39] Obtaining a laboratory test for benzodiazepine blood levels can be useful in patients presenting with CNS depression or coma of unknown origin. Techniques available to measure blood concentrations include thin layer chromatography, gas liquid chromatography with or without a mass spectrometer, and radioimmunoassay.[11] Although blood benzodiazepine levels do not appear to be related to any toxicological effect or predictive of clinical outcome. Blood levels are therefore mainly used to confirm the diagnosis rather than being useful for the clinical management of the patient.[11][40]

Treatment

Flumazenil is a benzodiazepine antagonist which can reverse the effects of benzodiazepines, although its use following benzodiazepine overdose is controversial.

Medical observation and supportive care are the mainstay of treatment of benzodiazepine overdose.[41] Although benzodiazepines are absorbed by activated charcoal,[42] gastric decontamination with activated charcoal is not beneficial in pure benzodiazepine overdose as the risk of adverse effects would outweigh any potential benefit from the procedure. It is only recommended if benzodiazepines have been taken in combination with other drugs that may benefit from decontamination.[43] Gastric lavage (stomach pumping) or whole bowel irrigation are similarly not recommended.[43] Enhancing elimination of the drug with hemodialysis, hemoperfusion, or forced diuresis is unlikely to be beneficial as these procedures have little effect on the clearance of benzodiazepines due to their large volume of distribution and lipid solubility.[43]

Supportive measures

Supportive measures include observation of vital signs, especially Glasgow Coma Scale and airway patency. IV access with fluid administration and maintenance of the airway with intubation and artificial ventilation may be required if respiratory depression or pulmonary aspiration occurs.[43] Supportive measures should be put in place prior to administration of any benzodiazepine antagonist in order to protect the patient from both the withdrawal effects and possible complications arising from the benzodiazepine. A determination of possible deliberate overdose should be considered with appropriate scrutiny, and precautions taken to prevent any attempt by the patient to commit further bodily harm.[44][45] Hypotension is corrected with fluid replacement, although catecholamines such as norepinephrine or dopamine may be required to increase blood pressure.[11] Bradycardia is treated with atropine or an infusion of norepinephrine to increase coronary blood flow and heart rate.[11]

Flumazenil

Flumazenil (Anexate) is a competitive benzodiazepine receptor antagonist that can be used as an antidote for benzodiazepine overdose. Its use, however, is controversial as it has numerous contraindications.[3][46] It is contraindicated in patients who are on long-term benzodiazepines, those who have ingested a substance that lowers the seizure threshold, or in patients who have tachycardia, widened QRS complex on ECG, anticholinergic signs, or a history of seizures.[47] Due to these contraindications and the possibility of it causing severe adverse effects including seizures, adverse cardiac effects, and death,[48][49] in the majority of cases there is no indication for the use of flumazenil in the management of benzodiazepine overdose as the risks generally outweigh any potential benefit of administration.[3][43] It also has no role in the management of an unknown overdoses.[5][46] Additionally, if full airway protection has been achieved, a good outcome is expected and therefore flumazenil administration is unlikely to be required.[50]

Flumazenil is very effective at reversing the CNS depression associated with benzodiazepines but is less effective at reversing respiratory depression.[46] One study found that only 10% of the patient population presenting with a benzodiazepine overdose are suitable candidates for flumazenil.[46] In this select population who are naive to and overdose solely on a benzodiazepine it can be considered.[51] Due to its short half life the duration of action of flumazenil is usually less than 1 hour and multiple doses may be needed.[46] When flumazenil is indicated the risks can be reduced or avoided by slow dose titration of flumazenil.[45] Due to risks and its many contraindications, flumazenil should only be administered after discussion with a medical toxicologist.[51][52]

Epidemiology

Benzodiazepines were implicated in 39% of suicides by drug poisoning in Sweden, with nitrazepam and flunitrazepam accounting for 90% of benzodiazepine implicated suicides, in the elderly over a period of 2 decades. In cases where benzodiazepines contributed to death but were not the sole cause; drowning, typically in the bath, was a common method used. Benzodiazepines were the predominant drug class in suicides in this review of Swedish death certificates. In 72% of the cases benzodiazepines were the only drug consumed. Thus many of deaths associated with benzodiazepine overdoses may not be a direct result of the toxic effects but due to being combined with either other drugs or used as a tool to complete suicide using a different method, e.g. drowning.[53]

In a Swedish retrospective study of deaths of 1987, when temazepam was still available in Sweden, in 159 of 1587 autopsy cases benzodiazepines were found. Temazepam was the most frequent benzodiazepine detected in the autopsy's. In 44 of the 159 cases the cause of death was natural causes or unclear. The remaining 115 deaths were due to accidents (N = 16), suicide (N = 60), drug addiction (N = 29) or alcoholism (N = 10). In a comparison of suicides and natural deaths, the concentrations of temazepam, flunitrazepam and nitrazepam (sleeping medications) were significantly higher among the suicides. In four cases temazepam was the sole cause of death.[54]

In Australia a study of 16 deaths associated with toxic concentrations of benzodiazepines during the period of 5 years leading up to July 1994 found preexisting natural disease as a feature of 11 cases, 14 cases were suicides. Cases where other drugs, including ethanol, had contributed to the death were excluded. In the remaining five cases, death was caused solely by benzodiazepines. Temazepam was the most prevalent drug detected, followed by nitrazepam, oxazepam and flunitrazepam in that order.[55] A review of self poisonings of 12 months 1976 - 1977 in Auckland, New Zealand, found benzodiazepines implicated in 40% of the cases with temazepam accounting for approximately 70% of benzodiazepine poisonings.[56] A 1993 British study found temazepam to have the highest number of deaths per million prescriptions among medications commonly prescribed in the 1980s (11.9, versus 5.9 for benzodiazepines overall, taken with or without alcohol).[57]

References

  1. ^ Dart, Richard C. (1 December 2003). Medical Toxicology (3rd ed.). USA: Lippincott Williams & Wilkins. p. 811. ISBN 978-0781728454.
  2. ^ Höjer J, Baehrendtz S, Gustafsson L (1989). "Benzodiazepine poisoning: experience of 702 admissions to an intensive care unit during a 14-year period". J. Intern. Med. 226 (2): 117–22. PMID 2769176. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  3. ^ a b c Seger DL (2004). "Flumazenil--treatment or toxin". J. Toxicol. Clin. Toxicol. 42 (2): 209–16. doi:10.1081/CLT-120030946. PMID 15214628.
  4. ^ Taylor S, McCracken CF, Wilson KC, Copeland JR (1998). "Extent and appropriateness of benzodiazepine use. Results from an elderly urban community". Br J Psychiatry. 173 (5): 433–8. doi:10.1192/bjp.173.5.433. PMID 9926062. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  5. ^ a b Ngo AS, Anthony CR, Samuel M, Wong E, Ponampalam R (2007). "Should a benzodiazepine antagonist be used in unconscious patients presenting to the emergency department?". Resuscitation. 74 (1): 27–37. doi:10.1016/j.resuscitation.2006.11.010. PMID 17306436. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  6. ^ Jonasson B, Jonasson U, Saldeen T (2000). "Among fatal poisonings dextropropoxyphene predominates in younger people, antidepressants in the middle aged and sedatives in the elderly". J. Forensic Sci. 45 (1): 7–10. PMID 10641912. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  7. ^ Relative toxicity of benzodiazepines in overdose
  8. ^ Serfaty M, Masterton G (1993). "Fatal poisonings attributed to benzodiazepines in Britain during the 1980s". Br J Psychiatry. 163 (3): 386–93. doi:10.1192/bjp.163.3.386. PMID 8104653.
  9. ^ Buckley NA, Dawson AH, Whyte IM, McManus P, Ferguson N.Correlations between prescriptions and drugs taken in self-poisoning: Implications for prescribers and drug regulation.Med J Aust (in press)
  10. ^ Buckley NA, Dawson AH, Whyte IM, O'Connell DL. (1995). "[Relative toxicity of benzodiazepines in overdose.]". BMJ. 310 (6974): 219–21. PMC 2548618. PMID 7866122.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  11. ^ a b c d e f g h i j k Gaudreault P, Guay J, Thivierge RL, Verdy I (1991). "Benzodiazepine poisoning. Clinical and pharmacological considerations and treatment". Drug Saf. 6 (4): 247–65. doi:10.2165/00002018-199106040-00003. PMID 1888441.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  12. ^ Wolf BC, Lavezzi WA, Sullivan LM, Middleberg RA, Flannagan LM (2005). "Alprazolam-related deaths in Palm Beach County". Am J Forensic Med Pathol. 26 (1): 24–7. doi:10.1097/01.paf.0000153994.95642.c1. PMID 15725773.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  13. ^ a b Sunter JP, Bal TS, Cowan WK (1988). "Three cases of fatal triazolam poisoning". BMJ. 297 (6650): 719. doi:10.1136/bmj.297.6650.719. PMC 1834083. PMID 3147739. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  14. ^ N A Buckley, A H Dawson, IM Whyte, D L O'Connell (1995). "Relative toxicity of benzodiazepines in overdose". British Medical Journal (BMJ). 310 (6974): 219. PMC 2548618. PMID 7866122.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  15. ^ Charlson F, Degenhardt L, McLaren J, Hall W, Lynskey M (2009). "A systematic review of research examining benzodiazepine-related mortality". Pharmacoepidemiol Drug Saf. 18 (2): 93–103. doi:10.1002/pds.1694. PMID 19125401. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  16. ^ Dietze P, Jolley D, Fry C, Bammer G (2005). "Transient changes in behaviour lead to heroin overdose: results from a case-crossover study of non-fatal overdose". Addiction. 100 (5): 636–42. doi:10.1111/j.1360-0443.2005.01051.x. PMID 15847621. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  17. ^ Hammersley R (1995). "Drugs associated with drug-related deaths in Edinburgh and Glasgow, November 1990 to October 1992". Addiction. 90 (7): 959–65. doi:10.1046/j.1360-0443.1995.9079598.x. PMID 7663317. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  18. ^ Ticku MK, Burch TP, Davis WC (1983). "The interactions of ethanol with the benzodiazepine-GABA receptor-ionophore complex". Pharmacol. Biochem. Behav. 18. Suppl 1: 15–8. PMID 6138771.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  19. ^ Kudo K, Imamura T, Jitsufuchi N, Zhang XX, Tokunaga H, Nagata T (1997). "Death attributed to the toxic interaction of triazolam, amitriptyline and other psychotropic drugs". Forensic Sci. Int. 86 (1–2): 35–41. doi:10.1016/S0379-0738(97)02110-5. PMID 9153780. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  20. ^ Rogers, Wo; Hall, Ma; Brissie, Rm; Robinson, Ca (1997). "Detection of alprazolam in three cases of methadone/benzodiazepine overdose". Journal of forensic sciences. 42 (1): 155–6. ISSN 0022-1198. PMID 8988593. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  21. ^ Brødsgaard I (1995). "Two cases of lethal nitrazepam poisoning". Am J Forensic Med Pathol. 16 (2): 151–3. doi:10.1097/00000433-199506000-00015. PMID 7572872. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  22. ^ Reidenberg MM, Levy M, Warner H, Coutinho CB, Schwartz MA, Yu G, Cheripko J (1978). "Relationship between diazepam dose, plasma level, age, and central nervous system depression". Clin. Pharmacol. Ther. 23 (4): 371–4. PMID 630787. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  23. ^ a b c Wiley CC, Wiley JF (1998). "Pediatric benzodiazepine ingestion resulting in hospitalization". J. Toxicol. Clin. Toxicol. 36 (3): 227–31. doi:10.3109/15563659809028944. PMID 9656979.
  24. ^ Garnier R, Medernach C, Harbach S, Fournier E (1984). "[Agitation and hallucinations during acute lorazepam poisoning in children. Apropos of 65 personal cases]". Ann Pediatr (Paris) (in French). 31 (4): 286–9. PMID 6742700. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  25. ^ Berger R, Green G, Melnick A (1975). "Cardiac arrest caused by oral diazepam intoxication". Clin Pediatr (Phila). 14 (9): 842–4. doi:10.1177/000992287501400910. PMID 1157438. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  26. ^ Welch TR, Rumack BH, Hammond K (1977). "Clonazepam overdose resulting in cyclic coma". Clin. Toxicol. 10 (4): 433–6. doi:10.3109/15563657709046280. PMID 862377.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  27. ^ Höjer J, Baehrendtz S, Gustafsson L (1989). "Benzodiazepine poisoning: experience of 702 admissions to an intensive care unit during a 14-year period". J. Intern. Med. 226 (2): 117–22. PMID 2769176. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  28. ^ Busto U, Kaplan HL, Sellers EM (1980). "Benzodiazepine-associated emergencies in Toronto". Am J Psychiatry. 137 (2): 224–7. PMID 6101526. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  29. ^ a b Greenblatt DJ, Allen MD, Noel BJ, Shader RI (1977). "Acute overdosage with benzodiazepine derivatives". Clin. Pharmacol. Ther. 21 (4): 497–514. PMID 14802. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  30. ^ Lai SH (2006). "A survey of buprenorphine related deaths in Singapore". Forensic Sci Int. 162 (1–3): 80–6. doi:10.1016/j.forsciint.2006.03.037. PMID 16879940. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  31. ^ Koski A, Ojanperä I, Vuori E (2003). "Interaction of alcohol and drugs in fatal poisonings". Hum Exp Toxicol. 22 (5): 281–7. doi:10.1191/0960327103ht324oa. PMID 12774892. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  32. ^ Wishart, David (2006). "Triazolam". DrugBank. Retrieved 2006-03-23.
  33. ^ Hung DZ, Tsai WJ, Deng JF (1992). "Anterograde amnesia in triazolam overdose despite flumazenil treatment: a case report". Hum Exp Toxicol. 11 (4): 289–90. doi:10.1177/096032719201100410. PMID 1354979. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  34. ^ National Treatment Agency for Substance Misuse (2007). "Drug misuse and dependence - UK guidelines on clinical management" (PDF). United Kingdom: Department of Health. {{cite web}}: Cite has empty unknown parameter: |month= (help)
  35. ^ Pulce C, Mollon P, Pham E, Frantz P, Descotes J (1992). "Acute poisonings with ethyle loflazepate, flunitrazepam, prazepam and triazolam in children". Vet Hum Toxicol. 34 (2): 141–3. PMID 1354907. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  36. ^ Rumpl E (1988). "Short latency somatosensory evoked potentials and brain-stem auditory evoked potentials in coma due to CNS depressant drug poisoning. Preliminary observations". Electroencephalography and clinical neurophysiology. 70 (6): 482–9. doi:10.1016/0013-4694(88)90146-0. PMID 2461282. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  37. ^ Pasinato, E; Franciosi, A; De, Vanna, M (1983). ""Alpha pattern coma" after poisoning with flunitrazepam and bromazepam. Case description". Minerva psichiatrica. 24 (2): 69–74. ISSN 0374-9320. PMID 6140613. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  38. ^ Carroll WM, Mastiglia FL (1977). "Alpha and beta coma in drug intoxication". Br Med J. 2 (6101): 1518–9. doi:10.1136/bmj.2.6101.1518-a. PMC 1632784. PMID 589310. {{cite journal}}: Unknown parameter |month= ignored (help)
  39. ^ Perry HE, Shannon MW (1996). "Diagnosis and management of opioid- and benzodiazepine-induced comatose overdose in children". Curr. Opin. Pediatr. 8 (3): 243–7. doi:10.1097/00008480-199606000-00010. PMID 8814402. {{cite journal}}: Unknown parameter |month= ignored (help)
  40. ^ Jatlow P, Dobular K, Bailey D (1979). "Serum diazepam concentrations in overdose. Their significance". Am. J. Clin. Pathol. 72 (4): 571–7. PMID 40432. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  41. ^ Welch TR, Rumack BH, Hammond K (1977). "Clonazepam overdose resulting in cyclic coma". Clin. Toxicol. 10 (4): 433–6. doi:10.3109/15563657709046280. PMID 862377.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  42. ^ el-Khordagui LK, Saleh AM, KhalIl SA (1987). "Adsorption of benzodiazepines on charcoal and its correlation with in vitro and in vivo data". Pharm Acta Helv. 62 (1): 28–32. PMID 2882522.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  43. ^ a b c d e Whyte, IM (2004). "Benzodiazepines". Medical toxicology. Philadelphia: Williams & Wilkins. pp. 811–22. ISBN 0-7817-2845-2.
  44. ^ Buckley NA, Dawson AH, Whyte IM, O'Connell DL (28 January 1995). "Relative toxicity of benzodiazepines in overdose". BMJ. 310 (6974): 219–21. PMC 2548618. PMID 7866122.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  45. ^ a b Weinbroum AA, Flaishon R, Sorkine P, Szold O, Rudick V (1997). "A risk-benefit assessment of flumazenil in the management of benzodiazepine overdose". Drug Saf. 17 (3): 181–96. doi:10.2165/00002018-199717030-00004. PMID 9306053. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  46. ^ a b c d e Nelson, LH (2006). "Antidotes in depth: Flumazenil". Goldfrank's toxicologic emergencies (8th ed.). New York: McGraw-Hill. pp. 1112–7. ISBN 0-07-147914-7. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  47. ^ Spivey WH (1992). "Flumazenil and seizures: analysis of 43 cases". Clin Ther. 14 (2): 292–305. PMID 1611650.
  48. ^ Marchant B, Wray R, Leach A, Nama M (1989). "Flumazenil causing convulsions and ventricular tachycardia". BMJ. 299 (6703): 860. doi:10.1136/bmj.299.6703.860-b. PMC 1837717. PMID 2510872. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  49. ^ Burr W, Sandham P, Judd A (1989). "Death after flumazepil". BMJ. 298 (6689): 1713. doi:10.1136/bmj.298.6689.1713-a. PMC 1836759. PMID 2569340. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  50. ^ Hoffman RS, Goldfrank LR (1995). "The poisoned patient with altered consciousness. Controversies in the use of a 'coma cocktail'". JAMA. 274 (7): 562–9. doi:10.1001/jama.274.7.562. PMID 7629986. {{cite journal}}: Unknown parameter |month= ignored (help)
  51. ^ a b Nelson LH, Flomenbaum N, Goldfrank LR, Hoffman RL, Howland MD, Neal AL (2006). "Sedative-hypnotic agents". Goldfrank's toxicologic emergencies (8th ed.). New York: McGraw-Hill. pp. 929–51. ISBN 0-07-147914-7.{{cite book}}: CS1 maint: multiple names: authors list (link)
  52. ^ Thomson JS, Donald C, Lewin K (2006). "Use of Flumazenil in benzodiazepine overdose". Emerg Med J. 23 (2): 162. PMC 2564056. PMID 16439763. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  53. ^ Carlsten, A (2003). "The role of benzodiazepines in elderly suicides". Scand J Public Health. 31 (3): 224–8. doi:10.1080/14034940210167966. PMID 12850977. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  54. ^ Ericsson HR (November 10, 1993). "[Benzodiazepine findings in autopsy material. A study shows interacting factors in fatal cases]". Läkartidningen. 90 (45): 3954–7. PMID 8231567. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  55. ^ Drummer OH (1996). "Sudden death and benzodiazepines". Am J Forensic Med Pathol. 17 (4): 336–42. doi:10.1097/00000433-199612000-00012. PMID 8947361. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  56. ^ Large RG (1978). "Self-poisoning in Auckland reconsidered". N. Z. Med. J. 88 (620): 240–3. PMID 31581. {{cite journal}}: Unknown parameter |month= ignored (help)
  57. ^ Serfaty M, Masterton G (1993). "Fatal poisonings attributed to benzodiazepines in Britain during the 1980s". Br J Psychiatry. 163 (3): 386–93. doi:10.1192/bjp.163.3.386. PMID 8104653.