Recommended Dose of Ondansetron ODT for a 3-Year-Old Child Weighing 17 kg
The recommended dose of ondansetron ODT for a 3-year-old child weighing 17 kg is 2.55 mg (0.15 mg/kg), which can be rounded to 4 mg (one 4 mg ODT tablet). 1
Dosing Guidelines
- For children weighing 15-23 kg, the recommended dose of ondansetron is 0.15 mg/kg or 45 mg twice daily for treatment purposes 1
- For a 17 kg child, this calculates to 2.55 mg per dose (17 kg × 0.15 mg/kg = 2.55 mg) 1
- Since ondansetron ODT typically comes in 4 mg and 8 mg tablets, the practical dose would be one 4 mg ODT tablet 2
Administration Considerations
- Ondansetron ODT (oral dissolving tablet) is preferred over oral solution in children with vomiting, as it has been shown to cause less early vomiting (2.7% vs 9.5%) 3
- The tablet should be placed on the tongue where it will dissolve rapidly without requiring water 2
- No dosage adjustment is needed based on frequency of administration for acute conditions 4
Clinical Efficacy
- A single oral dose of ondansetron has been shown to reduce the risk of recurrent vomiting, need for IV fluids, and hospital admissions in children with acute gastroenteritis 5
- Research shows that within the dose range of 0.13-0.26 mg/kg, higher doses of ondansetron were not superior to lower doses, nor were they associated with increased side effects 4
- In primary care settings, ondansetron decreased the proportion of children who continued vomiting within 4 hours from 42.9% to 19.5% 6
Important Considerations
- Monitor for potential side effects, which may include headache, constipation, and diarrhea 2
- Ondansetron is generally well tolerated in children and rarely requires treatment withdrawal 2
- For antiemetic purposes in children, ondansetron has demonstrated superior efficacy compared to other antiemetics like metoclopramide 2
Practical Recommendation
- For this 3-year-old 17 kg child, administer one 4 mg ondansetron ODT tablet as a single dose 1
- If vomiting persists, the dose may be repeated every 8 hours as needed 1
- The ODT formulation is preferable as it dissolves on the tongue and doesn't require water, making it more suitable for a child with potential nausea or vomiting 3