Pediatric Dosing of Ondansetron by Weight
The recommended pediatric dose of ondansetron is 0.15 mg/kg intravenously every 4 hours (maximum 8 mg per dose) or 0.05-0.1 mg/kg intravenously for single-dose administration.
Intravenous (IV) Dosing
For Chemotherapy-Induced Nausea and Vomiting
- Standard dosing: 0.15 mg/kg IV every 4 hours for up to 4 doses 1
- Maximum single dose: 8 mg
- Alternative single high-dose regimen: 0.6 mg/kg IV (maximum 32 mg) has shown similar efficacy to the multiple standard-dose regimen 2
For Postoperative Nausea and Vomiting
- Optimal dose: 0.05-0.1 mg/kg IV 3, 4
- Research shows that 0.05 mg/kg is as effective as higher doses (0.1 mg/kg and 0.15 mg/kg) for postoperative nausea and vomiting prevention 4
Oral Dosing
For Acute Gastroenteritis
- Effective dose range: 0.13-0.26 mg/kg 5
- Studies show no significant difference in efficacy or side effects across this dose range 5
Dosing Considerations
Age-Based Considerations
- No specific dose adjustments needed based on age within the pediatric population
- For elderly patients (not applicable to pediatrics), no dosage adjustment is needed 6
Organ Impairment Considerations
- Hepatic impairment: No dosage adjustment needed for mild to moderate impairment
- Severe hepatic impairment: Do not exceed a total daily dose of 8 mg 6
- Renal impairment: No dosage adjustment recommended for any degree of renal impairment 6
Safety Considerations
Loading Doses
- Loading doses of 16 mg/m² (maximum 24 mg) IV appear safe in children, with minimal adverse events 7
- Most common adverse events include hypotension, fatigue, injection site reactions, headache, and dizziness 7
- Severe adverse events are rare (0.9%) and no life-threatening events were observed in studies 7
Dose Rounding
- Ondansetron should not be rounded further from the calculated dose 1
- Precise dosing is important for this medication to maintain safety and efficacy
Clinical Application by Setting
Low-Emetic Risk Antineoplastic Agents
- Ondansetron or granisetron monotherapy is recommended for pediatric patients 1
Moderate-Emetic Risk Antineoplastic Agents
- Two-drug combination of a 5-HT3 receptor antagonist (ondansetron) and dexamethasone is recommended 1
- If dexamethasone cannot be used, combine ondansetron with aprepitant 1
Minimal-Emetic Risk Antineoplastic Agents
- Routine antiemetic prophylaxis is not recommended 1
Key Points
- Ondansetron dosing should be weight-based in the pediatric population
- Lower doses (0.05 mg/kg) are effective for postoperative nausea and vomiting
- Higher doses (0.15 mg/kg) are typically used for chemotherapy-induced nausea and vomiting
- Single high-dose administration (0.6 mg/kg) may be as effective as multiple standard doses in chemotherapy patients
- Precise dosing without rounding is recommended for ondansetron