Illness script · Neurology

Status Epilepticus

Seizure lasting ≥5 minutes OR ≥2 seizures without return to baseline consciousness between them.

This illness script for Status Epilepticus covers predisposing factors, classic presentation, mechanism, workup, management, and the clinical pivots that separate it from look-alikes—written for USMLE Step 1 and clerkship reasoning.

Updated Jul 19, 2026All scripts

01

Predisposing factors

  • AED non-compliance is the #1 cause in known epileptics
  • Acute symptomatic: stroke, TBI, CNS infection, metabolic derangement
  • Alcohol withdrawal or toxin ingestion
  • Hyponatremia, hypoglycemia, hypocalcemia
  • Fever/CNS infection in children (febrile SE)
  • Prior history of epilepsy

02

Presentation

  • Convulsive SE: tonic-clonic activity >5 min with impaired consciousness
  • Non-convulsive SE (NCSE): altered mental status without obvious motor activity — requires EEG
  • May see eye deviation, subtle rhythmic limb jerking in NCSE
  • Post-ictal state should resolve; persistent AMS flags NCSE
  • Autonomic instability: tachycardia, hypertension, hyperthermia

03

Pathophysiology

  • Failure of seizure termination due to GABA-receptor internalization and NMDA-receptor upregulation
  • Excitotoxic neuronal injury begins within minutes of sustained seizure activity
  • Systemic consequences: hyperthermia, lactic acidosis, rhabdomyolysis, hypoxia
  • Refractory SE: GABA agonists become less effective over time — escalation required

04

Diagnostics

  • Fingerstick glucose immediately — rule out hypoglycemia
  • Labs: BMP, CBC, AED levels, tox screen, LFTs, ammonia
  • CT head after stabilization to rule out structural cause
  • LP if CNS infection suspected (after CT)
  • EEG — gold standard for NCSE diagnosis; continuous EEG in refractory cases
  • MRI superior for structural etiology once stabilized

05

Management

  • 0–5 min: ABCs, IV access, glucose (thiamine first if alcoholic), O2
  • 5–20 min (benzodiazepine phase): IV lorazepam 0.1 mg/kg (preferred) OR IM midazolam 10 mg
  • 20–40 min (second-line): IV fosphenytoin, valproate, or levetiracetam
  • 40+ min (refractory SE): intubation + IV midazolam/propofol/pentobarbital infusion
  • Treat underlying cause simultaneously (antibiotics for meningitis, correct electrolytes)
  • Avoid phenytoin in alcohol withdrawal SE — valproate or levetiracetam preferred

06

Clinical pivots

How to separate this script from the look-alikes that show up on exams and on the wards.

  • Psychogenic Non-Epileptic Seizure (PNES)

    Eyes closed during event, normal EEG during episode, no post-ictal confusion

  • Non-Convulsive Status Epilepticus

    AMS without motor activity — EEG required to confirm; can only be distinguished by EEG

  • Syncope with convulsive movements

    Brief (<30 sec) jerking, quick return to baseline, provoked by orthostatic trigger

  • Acute encephalopathy (metabolic/toxic)

    Fluctuating AMS without ictal EEG correlate; seizure-like movements absent on EEG

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Educational use only. This illness script is a study framework, not medical advice. Confirm decisions with current guidelines and your clinical supervisors.