Oral Diazepam for Preventing Febrile Seizures After Vaccination: A Randomized Controlled Trial

Abstract

Background: Febrile seizures are a common reason for pediatric emergency visits and may also occur after vaccination. Objectives: This study aimed to evaluate the effect of prophylactic oral diazepam on recurrence of febrile seizures after vaccination. Methods: This randomized clinical trial was conducted in 2023 among 128 children with a history of post-vaccination febrile seizures. Participants were randomly assigned to two equal groups. The intervention group received oral diazepam (1 mg/kg/day; maximum dose, 5 mg every 8 hours) for 48 hours after vaccination, whereas the control group received rectal diazepam only as rescue therapy. Outcomes were assessed on days 3, 7, and 14 after vaccination. Results: On day 7 after vaccination, febrile seizures occurred in 0% of the oral diazepam group and 9.37% of the control group, indicating a significant difference (P = 0.012). On day 14, febrile seizures were observed in 3.12% of the intervention group versus 12.5% of the control group (P = 0.048). Overall, seizure recurrence remained consistently lower in the diazepam group across follow-up visits. Regarding safety, adverse effects were reported in 18.75% of the intervention group and 9.37% of the control group, with no statistically significant difference (P = 0.12). Conclusions: Prophylactic oral diazepam may reduce the recurrence of post-vaccination febrile seizures in children. Larger studies are needed to confirm these findings.