Objective: We review retrospectively the clinical histories of patients who were immediately switched from carbamazepine (CBZ) to oxcarbazepine (OXC), being administered a minimum of 1.3 times the CBZ dosis in 2 daily dosis of OXC.
Method: The immediate switching was carried out in 22 paediatric cases. 17 patients were taking CBZ in monotherapy and 5 in politherapy. The change was made in 20 cases to lower the number of seizures (and to avoid side effects in 4 of them), and in 2 only to reduce drowsiness and fatigue. The average change was from 18.62 mg/kg of CBZ to 28.89 mg/kg of OXC. The medium change rate was 1.6:1 (maximum: 2:1).
Results: In 19 cases there were no side effects. With one boy, the essential tremor worsened and two girls became more tired and drowsy. Three experienced less drowsiness and one less weight increase. Twelve cases showed no seizure changes. Five cases became immediately seizure-free, three of them for a prolongated time. There was a reduction in seizure frequency in 2 cases, with posterior disappearance in one of them. Three cases experienced a reduction in seizure intensity. In two cases OXC was stopped after 24 seizure-free months. Fourteen patients were still taking OXC, 8 in monotherapy, with a mean follow-up of 31.5 months.
Conclusion: Given the potential benefits, ease and good tolerability, we advise trying with immediate switching to OXC, before adding another antiepileptic drug to CBZ.