Accidental methotrexate overdose leading to multisystem toxicity: A case report.

Background: Methotrexate (MTX) is an extensively used chemotherapeutic agent with well-characterized toxicity profiles. This case report describes the clinical presentation, management, and outcome of a patient presenting with severe MTX toxicity.

Case presentation: A 35-year-old Bangladeshi female was admitted on March 9, 2024, with severe mucosal ulcerations, painful skin lesions, and gastrointestinal bleeding after ingesting Methotrexate daily for 12 days by mistake instead of the medication prescribed to her. On physical examination, there was severe injury involving skin and mucosa. The laboratory results showed severe pancytopenia and liver and kidney function in derangement. There was gradual improvement with the prompt withdrawal of Methotrexate, Folinic Acid therapy, and supportive therapies; most of the laboratory values returned to normal by day 14.

Conclusion: This case was one of severe Methotrexate poisoning, leading to profound systemic toxicity. Thus, timely recognition, immediate drug withdrawal, and aggressive supportive care comprising Folinic Acid therapy and hydration played a major role in this patient's management.