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Last reviewed: 14 Mar 2025
Last updated: 09 Aug 2024

Summary

Definition

History and exam

Key diagnostic factors

  • presence of risk factors
  • miosis
  • bradypnoea
  • altered mental status
  • dramatic response to naloxone

Other diagnostic factors

  • fresh needle marks
  • drug paraphernalia nearby
  • decreased gastrointestinal motility
  • old track marks on arms and legs
  • pulmonary rales
  • frothy pink sputum
  • seizures
  • dysrhythmias

Risk factors

  • opioid use disorder and dependence
  • recent abstinence in chronic users
  • chronic pain

Diagnostic investigations

1st investigations to order

  • therapeutic trial of naloxone
  • Electrocardiogram (ECG)

Investigations to consider

  • chest x-ray
  • abdominal x-ray
  • abdominal CT scan
  • opioid urine screen
  • gas chromatography/mass spectrometry

Treatment algorithm

Contributors

Authors

Ruben Thanacoody, MD, FRCP

Consultant Physician and Clinical Toxicologist

Director, National Poisons Information Service (Newcastle)

Newcastle-upon-Tyne

UK

Disclosures

RT declares that he has no competing interests.

Acknowledgements

Dr Ruben Thanacoody would like to gratefully acknowledge Dr Dean Olsen, a previous contributor to this topic.

Disclosures

DO declares that he has no competing interests.

Peer reviewers

William Winter, MD

Staff

Gynecologic Oncologist

Northwest Cancer Specialists

Rose Quarter Cancer Center

Portland

OR

Disclosures

WW declares that he has no competing interests.

Anne-Maree Kelley, MD, MClinEd, FACEM

Director

Joseph Epstein Centre for Emergency Medicine Research

Western Health Sunshine Hospital

St Albans

Australia

Disclosures

AMK has received grant funding for research into intranasal delivery of naloxone in heroin overdose.

Andrew Stolbach, MD

Assistant Professor

Johns Hopkins University

Baltimore

MD

Disclosures

AS declares that he has no competing interests.

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