The antipyretic efficacies of ibuprofen (5 mg/kg dose) and acetaminophen (10 mg/kg dose) were compared in 70 outpatients (mean age, 2.1 years) with a history of febrile seizures by a randomized, multiple dose, double-blind clinical study conducted at the University Hospital, Sophia Children’s Hospital, and Erasmus University, Rotterdam, the Netherlands. Doses were given every 6 hours for 1 to 3 days, and rectal temperatures were recorded at 0, 2, 4, 6, 12, and 24 hours after the first dose. Ibuprofen reduced fever 0.5 degree C more than acetaminophen at 4 hours. The mean temperature was 0.26 degrees lower during ibuprofen treatment, and the highest temperature was 0.3 degrees lower. In a crossover trial and analysis, these differences in temperature were 0.66 and 0.36, respectively, in favor of ibuprofen. 
COMMENT. The risk of recurrence of febrile seizures might be reduced by early administration of antipyretic drugs. Ibuprofen appears to be superior to acetominophen in antipyretic efficacy, but an anticonvulsant effect remains to be determined.
In laboratory studies of antipyretic agents, aspirin and acetophenetidin failed to retard the rate of temperature rise induced by radiotherm diathermy in animals, and aspirin in doses of 600 mg/kg lowered the threshold convulsive temperature and exacerbated the febrile seizure. Antipyretics in small doses may facilitate heat loss and relieve discomfort attending fever, but large doses may possibly exacerbate the tendency to febrile seizures.