Intravenous granisetron for food protein-induced enterocolitis syndrome in Japanese children: A retrospective study

Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated gastrointestinal food allergy characterized by delayed-onset vomiting. Although ondansetron has demonstrated efficacy in managing FPIES-related symptoms, its use remains off-label in Japan. Granisetron hydrochloride (GH), another 5-HT₃ receptor antagonist, is approved in Japan for postoperative and chemotherapy-induced nausea and vomiting in children and is widely used in pediatric clinical settings. However, its use in FPIES has not been fully evaluated. This study aimed to assess the effectiveness and safety of intravenous GH in Japanese children undergoing oral food challenges (OFCs) for FPIES.

This retrospective study included pediatric patients who underwent OFCs for suspected or confirmed FPIES between January 2019 and September 2024 at a single center in Japan. Patients who developed vomiting received intravenous GH (40 μg/kg) and were subsequently monitored for symptom resolution, recurrence, the need for additional interventions, and any adverse events.

Among the 73 OFCs performed in 50 patients, 20 (27.4%) yielded a positive result, defined by the occurrence of vomiting. Of these, 18 cases from 16 patients received intravenous GH, and 16 OFCs from 14 patients were included in the final analysis. Vomiting resolved completely in 12 cases (75.0%), while four (25.0%) experienced only one additional vomiting episode. No cases required further antiemetic therapy or fluid resuscitation, and no GH-related adverse events were observed.

Intravenous GH was well-tolerated and may be effective in managing vomiting associated with FPIES during OFCs. These findings suggest that GH may be a practical therapeutic option, warranting further study.