Monoamine Oxidase Inhibitor (MAOI) Toxicity Workup

Updated: Feb 27, 2020
  • Author: Eddie Garcia, MD; Chief Editor: Michael A Miller, MD  more...
  • Print
Workup

Laboratory Studies

Standard laboratory tests for poisoned patients are indicated if the patient has significant symptoms. Such tests may include the following:

  • Rapid bedside glucose determination
  • Arterial blood gas 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)
  • Serum acetaminophen level and salicylate level - 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 is possibly helpful in assessing co-ingestions

Quantitative levels of monoamine oxidase inhibitors are not readily available and, therefore, are not clinically useful. Consider workup for hypertensive emergencies if any signs or symptoms are present.

Next:

Imaging Studies

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.

Previous