Methotrexate (MTX)-induced neurotoxicity is a serious adverse event associated with potentially deleterious neurological manifestations. 1-10 Proposed management of MTX-induced neurotoxicity includes supportive care, leucovorin, dextromethorphan, and aminophylline. 1,2,8-13 Dextromethorphan is a noncompetitive N-methyl-D-aspartate receptor antagonist that has been reported as a potential treatment modality at antitussive doses of 1-2 mg/kg (maximum 60 mg/dose) by mouth twice daily; however, dextromethorphan use is limited in patients unable to take enteral medications. 11-13