Effectiveness and safety of non-intravenous high-dose phenobarbital therapy for intractable epilepsy during childhood

High-dose phenobarbital (PB) therapy is effective for refractory status epilepticus. We reviewed medical records of patients with intractable partial epilepsies on whom performed non-intravenous high-dose PB therapy. Thirteen patients received PB rectally or orally at a dosage of 20–30 mg/kg/day initially, and the PB dosage was gradually reduced to a maintenance dosage of 5–10 mg/kg/day orally. We evaluated the effectiveness and safety of this procedure after 14 days at the maintenance dosage level. Twelve patients had partial seizures and one had secondary generalized seizures. In six of 13 patients (46%), seizure frequencies decreased more than 50%, and two of 13 patients (15%) became seizure free. In five of seven patients who were treated by continuous midazolam infusion therapy, we were able to discontinue the midazolam therapy. Adverse effects were found in seven of 13 patients. We were able to continue high-dose PB therapy in six patients because their adverse effects were transient and improved after a decrease in PB concentration, but we discontinued this therapy in the patient who developed Stevens–Johnson syndrome. Respiratory depression and hypotension were not found in our study. We conclude that high-dose PB therapy is effective and may be considered as an additional treatment for intractable partial epilepsy in childhood.