Initial anticonvulsant monotherapy in routine care of children and adolescents: levetiracetam fails more frequently than valproate and oxcarbazepine due to a lack of effectiveness.

Since anticonvulsants such as valproate or oxcarbazepine have quite a disadvantageous profile of possible adverse drug events (ADEs), safer alternatives are being sought. The newer anticonvulsant levetiracetam is often considered advantageous. We performed a chart review of children and adolescents aged from 0.5 to 16.9 years, who had been started on an initial monotherapy with levetiracetam, valproate, or oxcarbazepine between 2007 and 2011, in order to analyze the therapy's failure rate during the first year. We differentiated failure of monotherapy due to a lack of effectiveness and due to ADEs. No psychometric tests were performed. Lack of effectiveness and inacceptable ADEs were assumed according to the judgment of physicians and families. Anticonvulsive monotherapy failed in 29/61 (48 %) levetiracetam patients and in 18/49 (37 %) valproate patients (for focal and generalized epilepsies; n.s.). This was caused by a lack of effectiveness in 25/61 (41 %) levetiracetam patients and in 11/49 (22 %) valproate patients (p ≤ 0.05). A modification of therapy due to ADEs was performed in 4/61 (7 %) levetiracetam patients and in 7/49 (14 %) valproate patients (n.s.). An anticonvulsive monotherapy failed in 21/42 (50 %) patients treated with levetiracetam and in 10/34 (29 %) patients treated with oxcarbazepine (for focal epilepsies; n.s.). Changes of monotherapy were caused by a lack of effectiveness in 17/42 (40 %) of levetiracetam patients and in 6/34 (18 %) of oxcarbazepine patients (p ≤ 0.05). ADEs leading to changes in therapy were reported for 4/42 (10 %) of levetiracetam and 4/34 (12 %) of oxcarbazepine patients (n.s.). An initial monotherapy of levetiracetam failed more frequently due to a lack of effectiveness than a monotherapy with valproate or oxcarbazepine. We found no significant difference in therapy failure due to ADEs.