PassFinals
Paediatrics

Febrile convulsions

A seizure occurring with fever in a young child without evidence of CNS infection or another acute cause; most are brief and self-limiting, but the priority is seizure safety, assessment of the febrile illness and recognition of meningitis, prolonged, focal or recurrent seizures.

In a nutshell

Most febrile seizures are brief, generalised and self-limiting in children aged about 6 months to 5 or 6 years. Time the seizure, protect the child and never put anything in the mouth; a seizure lasting 5 minutes or more is an emergency. The key task is assessing the fever and excluding meningitis, encephalitis, sepsis or another acute cause.

Classic presentation

A young child with fever develops a generalised tonic-clonic seizure, is sleepy afterwards, then returns fully to baseline without focal neurological signs.

Key points

  • Simple febrile seizure: usually generalised, less than 15 minutes, once in 24 hours; complex features are focality, 15 minutes or longer or recurrence within 24 hours.
  • A seizure lasting 5 minutes or more is treated as convulsive status epilepticus, even though the simple-versus-complex classification uses a 15-minute duration feature.
  • Do not put anything in the child's mouth or restrain them; time the seizure, protect the head and use the recovery position afterwards.
  • Investigate the fever and neurological state, not the label: meningitis, encephalitis, sepsis, hypoglycaemia and poisoning must be considered when the child is unwell or atypical.
  • Lumbar puncture is not routine after a simple febrile seizure and is performed only when CNS infection is suspected and it is safe.
  • Antipyretics relieve distress but do not prevent febrile seizures; routine long-term antiseizure prophylaxis is not indicated after a simple event.

First-line investigation

Clinical assessment of seizure features, neurological recovery, fever source and serious-illness signs; targeted tests only when clinically indicated.

Management

Protect the child and stop prolonged seizure activity

  • Time the seizure, protect from injury, do not restrain or put anything in the mouth, and treat a convulsion lasting 5 minutes or more with the NICE status-epilepticus pathway.5,1,8,9

Assess the fever and neurological recovery

  • Use the fever traffic-light assessment, search for the infection source, examine for meningitis or encephalitis and confirm return to neurological baseline.6,7,1

Investigate selectively

  • Do not routinely perform EEG, imaging, lumbar puncture or extensive blood tests after a fully recovered simple febrile seizure; investigate complex, prolonged, focal or atypical events and serious-illness features.6,7,3

Escalate dangerous causes and recurrence

  • Arrange urgent paediatric review for meningism, shock, rash, focal signs, persistent altered consciousness, repeated seizures, age under 6 months or over 6 years, or an uncertain fever source.6,7,1

Reassure, comfort and safety-net

  • Use antipyretics only for distress, do not start routine prophylactic antiseizure medicine after a simple event, and give parents written first-aid and 999 escalation advice.6,5,1,2

Exam traps

  • A simple febrile seizure is not diagnosed solely by a temperature or a 24-hour symptom duration; the seizure pattern and recovery matter.
  • A seizure lasting 5 minutes needs emergency treatment even if it may later be classified as a simple seizure by the 15-minute feature.
  • Antipyretics are for comfort, not prevention.
  • Do not perform routine lumbar puncture, EEG or neuroimaging after a fully recovered simple febrile seizure.
  • Persistent altered consciousness, meningism, focal signs, non-blanching rash or age outside the usual range should trigger an alternative diagnosis pathway.

Illustrations

Simple vs complex febrile convulsionComparison table or diagram showing the defining features of simple and complex febrile seizures: generalised versus focal activity, duration, recurrence and return to baseline.PassFinals · original
Seizure first-aid for parentsIllustrated step-by-step guide for protecting a child during a febrile seizure, timing the event, avoiding restraint or objects in the mouth and placing the child in the recovery position afterwards.PassFinals · original
Red flags for fever plus seizureDiagram highlighting meningism, bulging fontanelle, non-blanching rash, persistent altered consciousness, focal deficit and prolonged or recurrent seizures that require urgent assessment.PassFinals · original

Key sources

  1. NHS: Febrile seizures (NHS condition information, current page)
  2. Epilepsy Action: Febrile seizures (UK patient and professional information, modified February 2026)
  3. NICE NG217: Diagnosis and assessment of epilepsy (NG217 section 1, updated 30 January 2025)
  4. Epilepsy Professional: Febrile seizures overview (UK professional update, Autumn 2025)
  5. NICE NG217: Status epilepticus and prolonged seizures (NG217 section 7, updated 30 January 2025)
  6. NICE NG143: Fever in under 5s, assessment and initial management (NG143 recommendations; current fever and antipyretic pathway)
  7. NICE NG240: Meningitis (bacterial) and meningococcal disease (NG240 recommendations; meningitis assessment, lumbar puncture and stabilisation)
  8. BNF: Midazolam (BNF medicine monograph)
  9. BNF: Diazepam (BNF medicine monograph)

This page is exam revision material, not medical advice, and must not be used for patient care. Always check drug doses against the BNF and current guidance. Full disclaimer.