Brief generalized nonconvulsive seizures (formerly petit mal) characterized by sudden staring and unresponsiveness for ~10 seconds with immediate recovery; classically associated with a generalized 3 Hz spike‑and‑wave pattern on EEG.
Common pediatric epilepsy syndrome (≈10–17% of childhood epilepsies) often mistaken for daydreaming or ADHD. Recognition is crucial, as untreated frequent lapses in awareness can impair learning and pose safety risks. Also frequently tested as a classic presentation of a child "staring off into space."
Multiple daily episodes of sudden staring with unresponsiveness, each lasting ~5–15 seconds and ending abruptly. The child has a blank stare (often with subtle eyelid flutter or lip-smacking) and immediately resumes activities with no postictal confusion.
Onset is typically in early school age (around 4–8 years old) in an otherwise normal child. Hyperventilation or drowsiness can precipitate seizures (often used as a provocation test in clinic). There is no aura or warning and no after-effects.
In juvenile absence epilepsy, absence seizures begin in adolescence (~10–15 years) and occur less frequently but tend to last longer; these patients often eventually have generalized tonic-clonic seizures as well.
Obtain an EEG with hyperventilation: typical absence seizures show generalized, symmetric 3 Hz spike-and-wave discharges that start and stop suddenly, confirming the diagnosis.
Distinguish from non-epileptic staring: during an absence episode, the child is unresponsive to touch or sound and cannot be interrupted (unlike daydreaming). If uncertain, use video-EEG monitoring; most "staring spells" in children are actually nonepileptic.
Be alert for atypical absence: longer lapses with gradual onset/offset and <2.5 Hz slow spike-waves on EEG suggest a different epilepsy syndrome (e.g., Lennox–Gastaut) and require a different approach.
Neuroimaging is usually normal in idiopathic absence epilepsy and is not indicated in straightforward cases.
Condition
Distinguishing Feature
Inattentiveness/Daydreaming (no seizure)
Occurs during boredom or fatigue; child can be refocused easily with tactile/verbal stimulation; no true impaired consciousness or abnormal EEG.
Focal impaired-awareness seizure
Previously "complex partial" seizure – often >1 minute with an aura and postictal confusion; may have focal automatisms; EEG shows focal onset (e.g., temporal lobe).
Atypical absence seizure
Longer spells with more gradual onset/termination, EEG <2.5 Hz slow spike-wave; usually in children with intellectual disability or known epilepsy syndrome (e.g., Lennox-Gastaut).
Ethosuximide – first-line for typical absence seizures (blocks thalamic T-type Ca²⁺ channels); highly effective for pure absence epilepsy.
Valproate – equally effective for absence seizures and preferred if there are generalized tonic-clonic seizures or juvenile onset. Use is limited in young females due to teratogenicity and cognitive side effects.
Others: Lamotrigine is a third-line option (some efficacy but lower success rates). Levetiracetam or topiramate may be used adjunctively. Avoid narrow-spectrum anti-seizure drugs (e.g., carbamazepine, phenytoin), which can exacerbate absence seizures.
Mnemonic: It SUX to have absence seizures → treat with ethosuximide (first-line).
No postictal confusion – kids "snap back" immediately after an absence ends (unlike other seizures).
Absence seizures starting <4 years old or with slow irregular spike-waves → consider atypical absence (possible Lennox–Gastaut or metabolic etiology) instead of classic absence epilepsy.
Development of other seizure types (e.g., tonic-clonic convulsions) → indicates broader generalized epilepsy (e.g., JAE) and need for broader therapy (valproate) plus safety precautions (no unsupervised swimming, driving restrictions until controlled).
Child with frequent brief "staring spells" → perform hyperventilation in office and order an EEG to evaluate for absence seizures.
If EEG shows generalized 3 Hz spike-and-wave and neurological exam is normal → diagnose absence epilepsy (imaging not routinely needed).
Begin ethosuximide for typical absence seizures. If seizures are not controlled or if any generalized convulsions occur, switch to or add valproate (especially for juvenile onset).
Ensure safety precautions until seizures are controlled (no solo swimming, heights; follow driving laws). Monitor response and side effects; many childhood cases remit at puberty, but some may require long-term therapy.
Grade-school child with frequent 10-second blank stares in class, unresponsive during episodes, immediately back to normal → absence seizures (petit mal).
Teenager with occasional staring spells and a recent generalized tonic-clonic seizure → juvenile absence epilepsy.
Case 1
A 6‑year‑old girl is noted to frequently "blank out" for ~10 seconds, not responding to her name and then quickly returning to normal.
Case 2
A 15‑year‑old boy with a history of occasional brief staring spells since age 12 has a generalized tonic-clonic seizure.
EEG showing generalized 3 Hz spike‑and‑wave discharges in a child with absence epilepsy.
