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Opioids/Benzodiazepines Poisoning Medication

  • Author: Christopher P Holstege, MD; Chief Editor: Zygmunt F Dembek, PhD, MPH, MS, LHD  more...
Updated: Sep 08, 2015

Medication Summary

If patients present following exposure 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)


DOC 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 agonists must be used with caution because, when used to treat a potentially life-threatening condition (eg, seizure disorder), they may exacerbate the underlying disorder. If a patient ingests a drug that lowers the seizure threshold, such as a cyclic antidepressant, reversal may result in seizure or status epilepticus. 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 as a diagnostic and therapeutic agent for unsubstantiated drug-associated coma is controversial. A positive response to small titratable doses may obviate the need for endotracheal (ET) intubation.

Flumazenil (Romazicon)


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

Contributor Information and Disclosures

Christopher P Holstege, MD Professor of Emergency Medicine and Pediatrics, University of Virginia School of Medicine; Chief, Division of Medical Toxicology, Center of Clinical Toxicology; Medical Director, Blue Ridge Poison Center

Christopher P Holstege, MD is a member of the following medical societies: American Academy of Clinical Toxicology, Medical Society of Virginia, Society of Toxicology, Wilderness Medical Society, European Association of Poisons Centres and Clinical Toxicologists, American Academy of Emergency Medicine, American College of Emergency Physicians, American College of Medical Toxicology, Society for Academic Emergency Medicine

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

Chief Editor

Zygmunt F Dembek, PhD, MPH, MS, LHD Associate Professor, Department of Military and Emergency Medicine, Adjunct Assistant Professor, Department of Preventive Medicine and Biometrics, Uniformed Services University of the Health Sciences, F Edward Hebert School of Medicine

Zygmunt F Dembek, PhD, MPH, MS, LHD is a member of the following medical societies: American Chemical Society, New York Academy of Sciences

Disclosure: Nothing to disclose.

Additional Contributors

Suzanne White, MD Medical Director, Regional Poison Control Center at Children's Hospital, Program Director of Medical Toxicology, Associate Professor, Departments of Emergency Medicine and Pediatrics, Wayne State University School of Medicine

Suzanne White, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Clinical Toxicology, American College of Epidemiology, American College of Medical Toxicology, American Medical Association, Michigan State Medical Society

Disclosure: Nothing to disclose.

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