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Status epilepticus
A convulsive seizure lasting 5 minutes or more, or repeated seizures without recovery in between, is status epilepticus: time is brain damage, so treatment is a fixed ladder — benzodiazepine, a second-line drug, then anaesthesia.
Why it matters in the exam
Questions present a continuing seizure in the emergency department or ambulance and ask for the next drug and its dose, the first steps (glucose, thiamine), and what to do when benzodiazepines have failed. Classic distractors are waiting for the seizure to stop on its own, giving too low a benzodiazepine dose, or choosing phenytoin for a toxin-induced seizure. A patient who does not wake after the jerking stops may be in non-convulsive status that only EEG can diagnose. In late pregnancy with hypertension the answer is magnesium, not a standard antiseizure drug.
Key points
- Convulsive status epilepticus is a seizure of 5 minutes or more or seizures without recovery between them.
- Start with stabilisation, glucose and thiamine, then a full-dose benzodiazepine.
- Second line: levetiracetam, fosphenytoin or valproate — similar efficacy.
- Refractory: intubation, anaesthetic infusion and continuous EEG.
- Special situations: magnesium in eclampsia, pyridoxine in isoniazid poisoning.
Summary table
| Stage and time | Treatment | Dose and details |
|---|---|---|
| 0 to 5 minutes: stabilise | Airway, oxygen, intravenous access, glucose check | Thiamine 100 mg intravenously before glucose when alcohol or malnutrition is suspected |
| 5 to 20 minutes: first line | Benzodiazepine: intravenous lorazepam, intravenous diazepam, or intramuscular midazolam | Lorazepam 0.1 mg/kg, maximum 4 mg per dose, may repeat once; intramuscular midazolam 10 mg above 40 kg |
| 20 to 40 minutes: second line | Intravenous levetiracetam, fosphenytoin or valproate — similar efficacy | Levetiracetam 60 mg/kg (up to 4500 mg); fosphenytoin 20 mg PE/kg; valproate 40 mg/kg (up to 3000 mg) |
| Over 40 minutes: refractory | Intubation and continuous infusion of midazolam, propofol or pentobarbital | Continuous EEG monitoring, treat the medical cause of the seizure |
| Special situations | Eclampsia — magnesium sulfate; isoniazid poisoning — pyridoxine; severe hyponatraemia — hypertonic saline | Avoid valproate in pregnancy and liver disease; phenytoin is unsuitable for toxin-induced seizures |
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Sources
- American Epilepsy Society Guideline: Treatment of Convulsive Status Epilepticus in Children and Adults, 2016 — Treatment algorithm by phase
- ILAE Task Force: A Definition and Classification of Status Epilepticus, 2015 — Operational time points t1 and t2
- Established Status Epilepticus Treatment Trial (ESETT, NEJM), 2019 — Second-line agents
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-06. The text may contain errors; when in doubt, check the source.