Fomepizole therapy for reversal of visual impairment after methanol poisoning: a case documented by visual evoked potentials investigation.

Essama Mbia, Jean-Jacques [UCL] Guerit, Jean-Michel [UCL] Haufroid, Vincent [UCL] Hantson, Philippe [UCL]

PURPOSE: To illustrate the safety and efficacy of fomepizole in a case of methanol poisoning with initial visual impairment. DESIGN: Interventional case report. METHODS: A 60-year-old man was admitted with blurred vision and changes in color perception 18 hours after ingesting 100 ml methanol. Fomepizole was chosen for antidotal therapy in combination with hemodialysis. Flash electroretinogram (fERG) and flash visual evoked potentials (fVEPs) examinations were obtained at the bedside 2 hours after admission and on days 1 and 8. The monocular pattern-reversal visual evoked potentials (pVEPs) were investigated on days 1 and 8. RESULTS: A complete reversal of visual impairment was achieved within 20 hours. An abnormal b-wave amplitude and an increased peak III latency at VEPs were present on admission and recovered within 24 hours. CONCLUSIONS: Fomepizole appeared safe and effective for a patient who had severe methanol poisoning presenting with visual impairment.