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Pediatric Monoamine Oxidase Inhibitor Toxicity Workup

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

Laboratory Studies

See the list below:

  • Rapid bedside glucose determination
  • ABG determination - Indicated if a compromise in oxygenation or ventilation is suspected
  • Lactate level - May be useful in phases 2 and 3 of an acute overdose to help determine end-organ perfusion
  • Determination of serum electrolyte, calcium, and magnesium levels - Calculation of the anion gap possibly helpful in screening for co-ingestions (see the Anion Gap calculator)
  • Evaluation of serum acetaminophen and salicylate levels - Indicated in intentional overdoses
  • Screening for serum levels of alcohol (ethanol, methanol, isopropyl alcohol) - Indicated if alcohol ingestion is clinically suspected
  • Urine pregnancy test - Indicated in all women of childbearing age
  • Urinalysis and urine pH determination - May be useful in the setting of rhabdomyolysis
  • Urine drug screening - Comprehensive drug screening and screening for commonly abused drugs possibly helpful in assessing co-ingestions
  • Evaluation of levels of specific monoamine oxidase inhibitor (MAOI) drugs - Not readily available and, therefore, not clinically useful

Imaging Studies

See the list below:

  • Chest radiography is indicated if aspiration is a concern.
  • Perform postintubation chest radiography to evaluate the position of the endotracheal tube in relation to the carina if respiratory support is needed.

Other Tests

See the list below:

  • Sinus tachycardia is the most common ECG abnormality.
  • Nonspecific T-wave changes are also reported.


Endotracheal intubation is required in any patient with a decreasing level of consciousness or signs of impending respiratory failure. Secure the airway before administering activated charcoal or performing gastric lavage in patients with compromised mental status.

Venous access should be obtained. Two large-bore peripheral intravenous lines should be placed in symptomatic patients. Central access may be necessary for the infusion of vasoactive agents.

Gastric lavage is reserved for patients with life-threatening overdoses (2-3 mg/kg) who present within 1 hour of the ingestion. Note the following:

  • A large-bore orogastric tube should be used
  • Isotonic sodium chloride solution is preferred to water in young children because of the risk of an electrolyte imbalance and water intoxication
  • Before proceeding with any decontamination, secure the patient's airway

Foley catheterization of the bladder is indicated to assess urine output, especially in the setting of hemodynamic compromise or rhabdomyolysis.

Arterial line placement is indicated for continuous blood pressure monitoring and frequent blood sampling in patients with a severe ingestion and cardiovascular instability.

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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