What is the recommended dose of midazolam (benzodiazepine) for managing febrile convulsions?

Midazolam Dosing for Febrile Convulsions

For acute febrile convulsions in children, administer intranasal midazolam 0.2 mg/kg (maximum 6 mg per dose) as the preferred first-line treatment when intravenous access is unavailable, or intravenous midazolam 0.1 mg/kg if IV access is established. 1, 2

Route-Specific Dosing Algorithm

Intranasal Route (Preferred when IV access unavailable)

• Dose: 0.2 mg/kg (maximum 6 mg per dose) 2
• This route achieves faster overall time to seizure cessation compared to establishing IV access for diazepam 2
• Equally effective as IV diazepam with mean seizure control time of 6.1 minutes from administration 2
• Can be administered by families at home with appropriate training 2

Intravenous Route (When IV access available)

• Initial dose: 0.05-0.10 mg/kg administered slowly over 2-3 minutes (maximum single dose: 5 mg) 1, 3
• Peak effect occurs at 3-5 minutes after administration 1, 3
• May repeat every 10-15 minutes if seizures persist 1, 3
• Observe for 3-5 minutes between doses to avoid oversedation 1

Intramuscular Route (Alternative)

• Dose: 0.2 mg/kg (maximum 6 mg per dose) 1
• May repeat every 10-15 minutes if needed 1
• Less effective than IV route but more effective than intranasal in real-world data 4

Escalation for Refractory Seizures

If febrile convulsion persists despite initial bolus doses:

• Loading dose: 0.15-0.20 mg/kg IV 1, 3
• Follow with continuous infusion starting at 1 μg/kg/min (0.06 mg/kg/hr) 3
• Titrate by increments of 1 μg/kg/min every 15 minutes up to maximum 5 μg/kg/min (0.3 mg/kg/hr) until seizures stop 1, 3

Critical Safety Monitoring

Respiratory Precautions

• Increased risk of apnea, especially when combined with other sedatives 1, 3
• Monitor oxygen saturation continuously 1, 3
• Be prepared to provide respiratory support regardless of administration route 1, 3
• Have flumazenil available to reverse life-threatening respiratory depression, though this will also reverse anticonvulsant effects 1, 3

Common Pitfalls to Avoid

• Do not underdose: Lower doses of midazolam are ineffective for seizure control 1
• Avoid rapid IV administration: Give over 2-3 minutes to prevent oversedation and hypotension 1, 3
• Watch for paradoxical agitation, especially in younger children 1
• Do not delay treatment attempting IV access when intranasal route is immediately available 2

Evidence Quality Considerations

The American Academy of Pediatrics guidelines provide the foundational dosing framework 1, supported by randomized trial data showing intranasal midazolam (0.2 mg/kg) controls 88% of prolonged febrile convulsions with faster overall treatment times than IV diazepam 2. A Cochrane review confirms intranasal midazolam's effectiveness as equivalent to IV diazepam for febrile seizures 5. Real-world data from 7,634 patients demonstrates that higher doses are associated with better seizure control 4, reinforcing the importance of adequate dosing per guidelines rather than underdosing out of excessive caution.