Antipyretic agents for preventing recurrences of febrile seizures: randomized controlled trial.

OBJECTIVE To evaluate the efficacy of different antipyretic agents and their highest recommended doses for preventing febrile seizures. DESIGN Randomized, placebo-controlled, double-blind trial. SETTING Five hospitals, each working as the only pediatric hospital in its region. PARTICIPANTS A total of 231 children who experienced their first febrile seizure between January 1, 1997, and December 31, 2003. The children were observed for 2 years. INTERVENTIONS All febrile episodes during follow-up were treated first with either rectal diclofenac or placebo. After 8 hours, treatment was continued with oral ibuprofen, acetaminophen, or placebo. MAIN OUTCOME MEASURE Recurrence of febrile seizures. RESULTS The children experienced 851 febrile episodes, and 89 of these included a febrile seizure. Febrile seizure recurrences occurred in 54 of the 231 children (23.4%). There were no significant differences between the groups in the main measure of effect, and the effect estimates were similar, as the rate was 23.4% (46 of 197) in those receiving antipyretic agents and 23.5% (8 of 34) in those receiving placebo (difference, 0.2; 95% confidence interval, -12.8 to 17.6; P = .99). Fever was significantly higher during the episodes with seizure than in those without seizure (39.7 degrees C vs 38.9 degrees C; difference, 0.7 degrees C; 95% confidence interval, -0.9 degrees C to -0.6 degrees C; P < .001), and this phenomenon was independent of the medication given. CONCLUSIONS Antipyretic agents are ineffective for the prevention of recurrences of febrile seizures and for the lowering of body temperature in patients with a febrile episode that leads to a recurrent febrile seizure.