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Pediatric Organophosphates Toxicity Medication

  • Author: William Freudenthal, MD; Chief Editor: Timothy E Corden, MD  more...
Updated: Sep 07, 2015

Medication Summary

Anticholinergic agents are important for controlling the life-threatening effects of organophosphate exposure. Initiate atropine therapy early to control secretions, bronchoconstriction, bronchospasm, and GI toxicity. Pralidoxime (2-PAM) is an oxime that reactivates cholinesterase, restoring respiratory and skeletal muscle strength. 2-PAM does not cross the blood-brain barrier; hence, the central effects are not reversed.


Anticholinergic agents

Class Summary

These agents are thought to work centrally by suppressing conduction in the vestibular cerebellar pathways. They may have an inhibitory effect on the parasympathetic nervous system. Anticholinergic agents also improve conduction through the AV node by reducing vagal tone by means of muscarinic receptor blockade.

Atropine IV/IM


Competitive antagonist of acetylcholine and other muscarinic agonists. Competes for common binding site on muscarinic receptor. Used to treat GI, pulmonary, and upper airway symptoms after known or suspected organophosphate exposure. Administer until cholinergic signs reverse. Large doses may be needed.


Cholinesterase reactivators

Class Summary

These medications are used as antidotes to reverse the inhibition of acetylcholinesterase (AChE). The effectiveness of oxime compounds is attributed to their 2-formyl-1-methylpyridinium ions.

2-PAM (Protopam)


Nucleophilic agent that reactivates phosphorylated AChE by binding to organophosphate molecule. Used to treat muscle weakness and respiratory muscle weakness in known or suspected exposure. Must be administered within 24 h, before organophosphate-cholinesterase bond ages. Earlier administered, better result. Effects should occur within 20-30 min.

Because it does not substantially relieve respiratory center depression or decrease muscarinic effects of AChE poisoning, concomitantly administer atropine to block effects of organophosphate poison on these areas. Signs of atropinization might occur earlier with addition of 2-PAM.

Contributor Information and Disclosures

William Freudenthal, MD Staff Physician, Department of Emergency Medicine, St. Vincent Hospital Indianapolis, IN

William Freudenthal, MD is a member of the following medical societies: American College of Emergency Physicians, Association of Military Surgeons of the US

Disclosure: Nothing to disclose.


Mark E Ralston, MD, MPH Staff Pediatrician, Naval Hospital Oak Harbor; Assistant Professor of Pediatrics, F Edward Hebert School of Medicine, Uniformed Services University of the Health Sciences

Mark E Ralston, MD, MPH is a member of the following medical societies: American Academy of Pediatrics

Disclosure: Nothing to disclose.

Specialty Editor Board

Mary L Windle, PharmD Adjunct Associate Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Nothing to disclose.

Jeffrey R Tucker, MD Assistant Professor, Department of Pediatrics, Division of Emergency Medicine, University of Connecticut School of Medicine, Connecticut Children's Medical Center

Disclosure: Received salary from Merck for employment.

Chief Editor

Timothy E Corden, MD Associate Professor of Pediatrics, Co-Director, Policy Core, Injury Research Center, Medical College of Wisconsin; Associate Director, PICU, Children's Hospital of Wisconsin

Timothy E Corden, MD is a member of the following medical societies: American Academy of Pediatrics, Phi Beta Kappa, Society of Critical Care Medicine, Wisconsin Medical Society

Disclosure: Nothing to disclose.

Additional Contributors

Michael E Mullins, MD Assistant Professor, Division of Emergency Medicine, Washington University in St Louis School of Medicine; Attending Physician, Emergency Department, Barnes-Jewish Hospital

Michael E Mullins, MD is a member of the following medical societies: American Academy of Clinical Toxicology, American College of Emergency Physicians

Disclosure: Received stock ownership from Johnson & Johnson for none; Received stock ownership from Savient Pharmaceuticals for none.

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