Single daily dosing versus divided dosing intravenous ondansetron to prevent chemotherapy-induced nausea and vomiting...

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.

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.

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.

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.