In a controlled study of two groups of patients treated with phenobarbital either intermittently at the time of febrile episodes or continuously, febrile seizures recurred in approximately 50 per cent. Control of the seizures was of equal but questionable degree in both groups. Dilantin failed to prevent recurrence of febrile seizures in 7 children treated continuously. Continued administration of anticonvul sant drugs is unwarranted in the prophylactic treatment of seizures which occur only in association with fever. Phenobarbital should be used intermittently in relatively large doses at the earliest signs of infection and as an adjunct to antipyretic therapy.