Neonatal seizures are defined as those occurring in the first 28 days of life of a full-term baby. Seizures in newborns may be subtle and are often more fragmentary and less coordinated than seizures in children or adults because the brain is still developing. Seizures can be tonic, clonic, myoclonic, or subclinical. Clinically, there may be sudden jerking of the whole body, stiffening and/or twitching of one limb or multiple limbs, gaze deviation, or changes in heart rate or respiratory rate. Events typically last 10 seconds to 2 minutes.

Neonatal seizures can result from infection, electrolyte abnormalities, brain malformations or injury (eg, perinatal stroke, hemorrhage, hypoxic ischemic injury), drug withdrawal, metabolic disorders, genetic disorders, or be idiopathic. Hypoxic-ischemic injury is the most common cause. Prognosis varies depending on the cause, from complete resolution of seizures to long-term cognitive and developmental issues and even death.