Acute methotrexate ingestions in adults: a report of serious clinical effects and treatments

Abstract

Objective. Limited reported data have reports effects after acute ingestion of methotrexate. Treatment recommendations do not differentiate between exposure routes. Our objective was to determine the frequency of significant toxicity effects and use of therapy after methotrexate ingestion in adults. Methods. We performed a retrospective study on adult cases reported to 6 poison centers over 6 years (2000-2005) which exceed 180,000 exposures/year. Variables collected included demographics, dosages ingested, coingestions, clinical effects, and therapies with outcomes. Results. Sixty-three patients examined over the 6-year period met inclusion criteria. No patient in the series received dialysis or died. The mean dose ingested for all patients was 24 mg (range 2.5-100 mg) and the mean dose for suicidal ingestions was 47.5 mg (12.5-100 mg). The most common clinical effects were abdominal pain, oral irritation, throat irritation, nausea, dizziness, and headache. Nine patients received folinic acid and 3 patients received sodium bicarbonate. No patient developed renal failure, bone marrow suppression, seizure, or coma. No patient died or received dialysis. Conclusion. In our series of patients from 6 poison centers over six years, 63 cases of acute adult methotrexate ingestions were reported. Methotrexate toxicity from ingestion in adults was uncommon and rarely toxic.