Anaphylactoid Reactions Suspected to Be Caused by Neostigmine in Pediatric Patients under General Anesthesia

: Anaphylactoid reaction is a rapid systemic allergic reaction to many kinds of allergen. The peak age of onset is in the forties and there are not many reports on anaphylactoid reactions in pediatric patients. We report two cases of pediatric patients who underwent surgical treatment on retinoblastoma and developed anaphylactoid reaction probably caused by neostigmine. General anesthesia was induced with fentanyl, sevoflurane, dinitrogen monoxide, and rocronium. The procedure was uneventfully completed. Just after the administration of neostigmine to reverse rocronium, the patients showed red flare on the face and chest, and wheezes were heard, but the vital signs were relatively stable. The rapid onset from the administration of neostigmine to the allergic reaction accompanied by skin and respiratory manifestations strongly suggested the anaphylactoid reaction to neostigmine.