Intranasal Midazolam for Emergent Seizure Management in a 3-Year-Old
For a 3-year-old child experiencing an active seizure in an emergent situation, administer intranasal midazolam at 0.2 mg/kg (maximum 6 mg per dose), though be prepared that this route may require redosing more frequently than intramuscular administration. 1, 2
Dosing Specifics
- Intranasal route: 0.2 mg/kg (maximum 6 mg per dose) 1, 2
- Can be repeated every 10-15 minutes if seizures persist 1
- For a typical 3-year-old (approximately 14-15 kg), this translates to roughly 2.8-3 mg per dose 1
Critical Safety Considerations
- Respiratory monitoring is mandatory: Continuous oxygen saturation monitoring must be maintained, as midazolam carries significant risk of respiratory depression, particularly when combined with other sedatives 1, 3
- Be prepared to provide respiratory support regardless of administration route 1, 3
- Have flumazenil readily available to reverse life-threatening respiratory depression, though recognize that flumazenil will also reverse anticonvulsant effects and may precipitate seizure recurrence 1, 3
Important Caveats About Intranasal Route
The intranasal route at 0.1 mg/kg has been shown to be inferior to other routes, with a 25% redosing rate compared to 14% for alternate routes 4. More recent evidence confirms that intranasal midazolam at 0.2 mg/kg is associated with 39% higher odds of requiring additional benzodiazepine doses compared to intramuscular administration 5. This suggests that while intranasal is convenient and painless, you should anticipate the need for repeat dosing more frequently than with IM administration 4, 5.
Alternative Routes if Intranasal Fails
- Intramuscular: 0.2 mg/kg (maximum 6 mg) - this is actually the preferred route based on efficacy data, with lower redosing rates 1, 5
- Intravenous: 0.05-0.1 mg/kg given over 2-3 minutes if IV access is available 1, 3
- Buccal: 0.3 mg/kg has shown 84% efficacy in stopping seizures within 10 minutes, though this is less commonly used 6
Follow-Up Treatment
Immediately administer a long-acting anticonvulsant (phenytoin 20 mg/kg IV over 10 minutes or fosphenytoin equivalent) after midazolam, as midazolam is rapidly redistributed and seizures often recur within 15-20 minutes 1, 3. The midazolam is only buying time for the definitive anticonvulsant to take effect 1.
Practical Pitfalls to Avoid
- Do not use 0.1 mg/kg for intranasal administration - this dose has been shown to be subtherapeutic 4
- Do not delay treatment to establish IV access - intranasal or IM routes allow for faster administration (median 7.3-7.8 minutes vs 13.1 minutes for IV) 5
- Do not administer as a rapid IV bolus if using IV route - give over 2-3 minutes to avoid oversedation and respiratory depression 1