Although phenobarbital (PB) is commonly used as a first-line antiseizure medication (ASM) for neonatal seizures, in 2015 we chose to replace it with levetiracetam (LEV), a third-generation ASM. Here, we compared the safety and efficacy of LEV and PB as first-line ASM, considering the years before and after modifying our treatment protocol.

We conducted a retrospective cohort study of 108 neonates with electroencephalography (EEG)-confirmed seizures treated with first-line LEV or PB in 2012 to 2020.

First-line ASM was LEV in 33 (31%) and PB in 75 (69%) neonates. The etiology included acute symptomatic seizures in 69% of cases (30% hypoxic-ischemic encephalopathy, 32% structural vascular, 6% infectious, otherwise metabolic) and neonatal epilepsy in 22% (5% structural due to brain malformation, 17% genetic). Forty-two of 108 (39%) neonates reached seizure freedom following first-line therapy. Treatment response did not vary by first-line ASM among all neonates, those with acute symptomatic seizures, or those with neonatal-onset epilepsy. Treatment response was lowest for neonates with a higher seizure frequency, particularly for those with status epilepticus versus rare seizures (P < 0.001), irrespective of gestational age, etiology, or EEG findings. Adverse events were noted in 22 neonates treated with PB and in only one treated with LEV (P < 0.001).

Our study suggests a potential noninferiority and a more acceptable safety profile for LEV, which may thus be a reasonable option as first-line ASM for neonatal seizures in place of PB. Treatment should be initiated as early as possible since higher seizure frequencies predispose to less favorable responses.