CBRNE - Opioids/Benzodiazepines Poisoning Medication

Updated: Jul 17, 2020
  • Author: Christopher P Holstege, MD; Chief Editor: Zygmunt F Dembek, PhD, MPH, MS, LHD  more...
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Medication Summary

If patients present after being exposed to aerosolized opioids or benzodiazepines, administration of the competitive antagonists naloxone and flumazenil, respectively, may be considered to reverse respiratory depression and coma.


Opioid antagonists

Class Summary

Opioid antagonists competitively inhibit the binding of opioid agonists to the opioid receptors. The goal of this therapy is reinstitution of adequate spontaneous ventilation. In patients presenting with sedation of unknown etiology, the cautious administration of naloxone may be both diagnostic and therapeutic. Even in high doses, naloxone has an excellent safety profile.

Naloxone (Narcan)

Drug-of-choice of opioid antagonists because of relatively short half-life, safety record, and availability.


Benzodiazepine antagonists

Class Summary

Flumazenil is a competitive benzodiazepine antagonist that reverses the effects of benzodiazepines. However, benzodiazepine antagonists must be used with caution because if given to a patient chronically exposed to benzodiazepines, the antagonist can precipitate benzodiazepine withdrawal. If a patient receives flumazenil and goes into withdrawal, seizures or status epilepticus can occur, necessitating treatment with a non-benzodiazepine agent such as a barbiturate. Flumazenil is not recommended for indiscriminate use before a complete evaluation. If patients present with coma following aerosolized benzodiazepines exposure, flumazenil may be considered if the patient has respiratory depression and no history of long-term benzodiazepine use or seizure disorder. Use of flumazenil as a diagnostic and therapeutic agent for unsubstantiated drug-associated coma is controversial. A positive response to small titratable doses of flumazenil or other benzodiazepine antagonist may obviate the need for endotracheal (ET) intubation in the setting of benzodiazepine toxicity.

Flumazenil (Romazicon)

Reverses effects of benzodiazepines in overdose by selectively antagonizing benzodiazepine receptor at GABA-A complex.