Organophosphate poisoning

Last reviewed: 6 Sep 2022
Last updated: 02 Dec 2021

Summary

Definition

History and exam

Key diagnostic factors

  • increased secretions
  • fasciculations
  • pinpoint pupils
  • distinctive odor
  • chest crackles and rhonchi
  • semiconscious/coma
More key diagnostic factors

Other diagnostic factors

  • visual disturbances
  • vomiting
  • influenza-like syndrome
  • urinary or fecal incontinence
  • proximal muscle weakness
  • abnormal deep tendon reflexes
  • abnormal heart rate
  • abnormal blood pressure
  • decreased respiration
  • hypothermia
  • seizures
  • delayed-onset central nervous system and peripheral (predominantly motor) neuropathy
Other diagnostic factors

Risk factors

  • pesticide availability
  • history of self-harm or recent interpersonal conflict
  • mental illness
  • alcohol or drug abuse
More risk factors

Diagnostic investigations

1st investigations to order

  • atropine therapeutic trial
  • plasma cholinesterase
  • red blood cell cholinesterase
More 1st investigations to order

Investigations to consider

  • chest x-ray
  • ECG
  • blood gases
More investigations to consider

Treatment algorithm

INITIAL

suspected poisoning

ACUTE

occupational or accidental poisoning

deliberate ingestion or terrorism/warfare with nerve agent

ONGOING

intermediate syndrome

organophosphate-induced delayed neuropathy

Contributors

Authors

Nicholas Buckley, MD, FRACP

Professor of Clinical Pharmacology

Pharmacology Department

Sydney Medical School

University of Sydney

Sydney

New South Wales

Australia

Disclosures

NB is an author of a number of references cited in this topic.

Peer reviewers

Steven B. Bird, MD, FACEP

Assistant Professor of Emergency Medicine

Division of Medical Toxicology

University of Massachusetts Medical School

North Worcester

MA

Disclosures

SBB declares that he has no competing interests.

Cynthia K. Aaron, MD, FACMT, FACEP

Program Director

Medical Toxicology

Regional Poison Center

Children's Hospital of Michigan

Detroit

MI

Disclosures

CKA holds stock in Merck Pharmaceuticals and is a paid consultant for ToxEd. She was briefly a paid consultant for Lexi-Comp.

Kent R. Olson, MD

Professor Medical Director

San Francisco Division

California Poison Control System

San Francisco

CA

Disclosures

KRO declares that he has no competing interests.

Ruben Thanacoody, MD, FRCP(Edin)

Consultant Physician and Clinical Toxicologist

National Poisons Information Service (Newcastle)

Newcastle-upon-Tyne

UK

Disclosures

RT declares that he has no competing interests.

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