Recommended Dose of Intramuscular Diazepam for Febrile Seizures
For febrile seizures when intravenous access is not available, intramuscular (IM) administration of diazepam is not recommended due to erratic absorption. Instead, rectal diazepam should be administered, or IM phenobarbital may be considered when rectal diazepam use is not possible due to medical or social reasons. 1
Management Options for Febrile Seizures
Acute Management:
- Febrile seizures typically affect children between 6-60 months of age and are self-limited, resolving spontaneously within 1-2 minutes 2
- For ongoing seizures requiring intervention, the WHO guidelines specifically advise against IM diazepam due to erratic absorption 1
- When IV access is available, IV benzodiazepines (lorazepam or diazepam) should be administered (lorazepam is preferred if available) 1
Prophylactic Management:
- Long-term anticonvulsant prophylaxis is not recommended for simple febrile seizures as the potential toxicities outweigh the relatively minor risks 1
- For complex febrile seizures (prolonged, focal, or multiple within 24 hours), prophylactic intermittent diazepam during febrile illness may be considered 1
- Oral diazepam given only during episodes of fever has shown a 44% reduction in the risk of febrile seizures per person-year in controlled trials 3
Important Considerations
Efficacy of Intermittent Diazepam:
- Studies show varying results regarding the effectiveness of intermittent oral diazepam:
- One study demonstrated an 82% reduction in febrile seizure risk when the medication was actually taken as prescribed 3
- Another study showed reduction in recurrence rates to 11.1% compared to 30.7% in untreated children 4
- However, some studies found no significant difference between diazepam and placebo groups 5
Side Effects and Cautions:
- Moderate side effects of oral diazepam include ataxia, lethargy, irritability, and hyperactivity 3, 5
- These side effects are generally reversible with dose reduction 3
- Transient side effects occurred in 36.8% of cases in one study 6
Common Pitfalls:
- Poor compliance is a major limitation to intermittent diazepam effectiveness - in one study, prophylactic treatment was correctly administered to only 1 of 15 children in the diazepam group 5
- Reasons for poor compliance include:
- Seizure being the first manifestation of fever
- Parents neglecting to give treatment
- Children refusing to take medication 5
- Antipyretics alone (acetaminophen or ibuprofen) do not prevent febrile seizure recurrence 1, 2, 7
Conclusion
While IM diazepam is specifically not recommended for febrile seizures due to erratic absorption, rectal diazepam or IM phenobarbital may be considered when IV access is unavailable 1. The American Academy of Pediatrics and WHO guidelines do not support routine anticonvulsant prophylaxis for simple febrile seizures 1.