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Four-year experience with methotrexate exposures

Frank LoVecchio1, Kenneth Katz, David Watts

  • 1Banner Good Samaritan Regional Poison Center, Maricopa Medical Center, Department of Emergency Medicine, Phoenix, AZ, USA. Frank.LoVecchio@bannerhealth.com

Journal of Medical Toxicology : Official Journal of the American College of Medical Toxicology
|September 30, 2008
PubMed
Abstract

Insights

Acute oral overdose of methotrexate (MTX) is uncommon. A review of poison center data found no significant toxicities in patients with unintentional MTX ingestion.

Area of Science:

  • Toxicology
  • Pharmacology
  • Clinical Medicine

Background:

  • Unintentional acute oral overdose of methotrexate (MTX) is infrequently documented in medical literature.
  • MTX is a common chemotherapeutic agent with known severe toxicity when administered intravenously.

Purpose of the Study:

  • To investigate the outcomes of acute oral MTX overdose.
  • To determine if oral MTX overdose presents similar toxicity risks as intravenous administration.

Main Methods:

  • A retrospective chart review was performed on human exposure calls related to MTX ingestions.
  • Data from 2000 to 2003 from a single Poison Center were analyzed, encompassing over 150,000 charts.

Main Results:

  • Thirteen patients met the inclusion criteria for the study.
  • The average ingested dose was 13.03 mg MTX (n=7), with an average patient age of 43 years (range: 20 months to 80 years).
  • No significant adverse toxicities were observed in the studied patients.

Conclusions:

  • Acute oral MTX overdose, whether unintentional or suicidal, does not appear to be associated with severe toxicity.
  • Findings suggest a lower risk profile for oral MTX ingestions compared to intravenous administration.

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