Toxicology USMLE Step 1 Practice Question
A 48-year-old woman with rheumatoid arthritis presents with severe oral ulcers, dysphagia, and fatigue. She mistakenly took methotrexate 25 mg daily for 2 weeks instead of weekly. Vital signs: BP 128/82, HR 102, RR 18, Temp 37.2°C, SpO2 98% on room air. Laboratory studies reveal WBC 2.1 K/μL, hemoglobin 9.8 g/dL, and platelets 85 K/μL. Mucous membranes show extensive ulceration. No hepatomegaly is appreciated on examination. Which medication is indicated as rescue therapy?
Answer choices
- AHydroxocobalamin
- BLeucovorinCorrect answer
- CPyridoxine
- DAtropine
- EProtamine sulfate
- FFolinic acid
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