Single daily dosing versus divided dosing intravenous ondansetron to prevent chemotherapy-induced nausea and vomiting among children: A comparative randomized double-blind controlled trial.

BACKGROUND: Chemotherapy-induced nausea and vomiting (CINV) is a common complication in cancer treatment. Ondansetron is an effective antiemetic drug widely used to prevent CINV; however, the effective administrative dosing strategies among pediatrics remain unclear. The study aimed to investigate clinical effectiveness of single daily dosing versus divided dosing ondansetron.

METHODS: In all, 194 children undergoing chemotherapy were randomized to receive either single daily dosing (0.3 mg/kg/dose) or divided dosing (0.15 mg/kg/dose every 8 hours) intravenous ondansetron for 24 hours. Clinical parameters including number of emesis episodes, nausea scores, appetite levels, parent's satisfaction, and adverse effects within 24 hours were analyzed.

RESULTS: No significant differences were found between the two dosing strategies concerning number of emesis episodes and parent's satisfaction. However, nonleukemic hematologic malignancies and concurrent administration of intrathecal methotrexate-hydrocortisone-cytarabine (IT-MHA) were associated with increased risk of acute-phase vomiting. Interestingly, none of the patients aged under 7 years, receiving divided dosing ondansetron, presented nausea symptoms compared with those receiving single daily dosing (p-value .034). No significant differences regarding headache were observed between the two dosing strategies and none of the patients experienced QTc prolongation.

CONCLUSION: Ondansetron administered as divided dosing should be considered among children aged under 7 years to prevent chemotherapy-induced nausea and among patients receiving low emetogenic chemotherapy to maintain their appetite. Both administrative dosing strategies were well tolerated with no significant adverse effects.