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Pediatric Monoamine Oxidase Inhibitor Toxicity Medication

  • Author: Soumya Ganapathy, MD; Chief Editor: Timothy E Corden, MD  more...
Updated: Jan 15, 2015

Decontamination agents

Class Summary

Consider activated charcoal decontamination in any patient who presents within one hour of the ingestion. Activated charcoal is used for drug adsorption and may be sufficient in mild-to-moderate toxicity. It is not absorbed and is excreted entirely through the GI tract.

Activated charcoal (Actidose-Aqua, Liqui-Char)


Emergency treatment in drug or chemical poisoning. Network of pores adsorbs 100-1000 mg of drug per gram of charcoal, decreasing GI absorption of the poison. Does not dissolve in water. In an acute overdose, most effective if given within 1 h of ingestion.

For maximum effect, administer within 30 min after ingesting poison. Sorbitol may be added to activated charcoal to improve its palatability. Sorbitol should never be used with multiple doses of charcoal, and never in children younger than 1 y.



Class Summary

Sympathomimetics produce direct or indirect stimulation of adrenergic receptors and have various actions depending on the specific receptors involved. Stimulation of alpha1-receptors produces smooth muscle contraction. In the cardiovascular system, this effect leads to vasoconstriction and increased blood pressure; in the eye, this effect leads to mydriasis. Other affected organs include the urinary sphincter and uterus. Stimulation of beta1-receptors has an inotropic effect and also increases the heart rate. Stimulation of beta2-receptors leads to smooth muscle relaxation and produces vasodilatation.

Hypotension is initially treated with isotonic fluids. Vasoactive agents are used if hypotension remains refractory despite the administration of intravenous fluids. Norepinephrine is preferred to dopamine because dopamine is an indirect sympathomimetic and can cause an uncontrollable and erratic release of norepinephrine.

Norepinephrine (Levophed)


Used to treat protracted hypotension after adequate fluid-volume replacement. Stimulates beta1- and alpha-adrenergic receptors, which in turn increase cardiac muscle contractility, heart rate, and vasoconstriction. As a result, systemic blood pressure and coronary blood-flow increase.



Class Summary

Do not use these drugs routinely. Often, the hypertension is transient and clinically insignificant. Avoid administering pure beta-blockers because they can produce an unopposed alpha effect.

Sodium nitroprusside (Nitropress)


Allows control of hypertensive emergency with rapid onset and short duration. Used as continuous infusion in closely monitored setting (ie, arterial access in pediatric ICU). Higher doses produce vasodilation and increases inotropic activity of the heart. May exacerbate myocardial ischemia by increasing heart rate.

Labetalol (Normodyne, Trandate)


Blocks beta1-, alpha-, and beta2-adrenergic receptor sites, decreasing blood pressure.

Phentolamine (Regitine)


Alpha1- and alpha2-adrenergic blocker that blocks circulating epinephrine and norepinephrine action, reducing hypertension that results from catecholamine effects on the alpha-receptors.



Class Summary

These agents are used to prevent seizures and terminate clinical and electrical seizure activity.

Lorazepam (Ativan)


Benzodiazepines can be used to treat agitation, seizures, or muscle rigidity.

Contributor Information and Disclosures

Soumya Ganapathy, MD Department of Emergency Medicine, Beverly Hospital

Soumya Ganapathy, MD is a member of the following medical societies: American College of Emergency Physicians

Disclosure: Nothing to disclose.


Frank A Maffei, MD, FAAP Associate Professor of Pediatrics, Temple University School of Medicine; Medical Director, Pediatric Intensive Care Unit, Janet Weis Children's Hospital at Geisinger Health System

Frank A Maffei, MD, FAAP 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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