First Seizure

College of Emergency Medicine 2010 GEM NET publication - Mx of First Seizure


  • Population studies: 4-7% lifetime risk of one seizure, 1% chance of epilepsy
  • 1.2% of ED attendances (of these 1/4 are first seizures)

In Cork:

  • All First seizures: 1/1000 population
  • Of these ½ unprovoked, ½ have a provoking insult/lesion e.g. :
    • electrolytes, hypoglycaemia
    • head injury, febrile illness, meningitis/encephalitis
    • alcohol and drug excess or withdrawal (younger patients)
    • stroke (older age group)
  • Seizure mimics: higher incidence than epilepsy

Of 1st seizures:

  • Overall, the risk of recurrence is 30–40% (max in the first 6/12 and falls to <10% after 2 years)
  • Recurrence more likely if brain imaging and/or EEG are abnormal

Collateral Hx is the most important ‘test’ in evaluating patients with suspected seizures


  • Glucose, U&E (↓Na+)
  • Consider Ca++, Mg++
  • ECG (incl. QTc) in all (TnI if doubt about seizure from collateral Hx)
  • In MUH, please record toxicology screen
  • ± Β-HCG
  • CXR, LP etc. as indicated


EEG should only be requested (iCM) by an EM consultant.


  • CT (or MRI) immediately if SOL suspected particularly if:
    • Hx of head injury trauma or risk of ICH (coagulopathy/anticoagulated)
    • Alcoholism (1st seizure only)
    • New focal deficit, persistent altered mentation or meningism
    • Partial or focal onset seizure
    • Persisting headache
    • Hx of malignancy, immunocompromise or HIV
  • Patients with repeated presentations to ED with seizures do not warrant repeated imaging unless new clinical signs or circumstances arise or obtundation is persistent
  • MRI (preferable to CT) if patient has fully recovered - request ‘Epilepsy Protocol’ MRI study

Disposition following 1st seizure


  • Confirm neurological recovery, no neuro deficit
  • Record serum Glucose, U&E (↓Na+)
  • Consider Ca++, Mg++
  • ECG in all cases (TnI if doubt about seizure from collateral history); confirm QTc
  • Admit to CDU if patient has recovered, no neuro. deficit & normal glucose / ECG
  • If patient is at significant risk of further seizures, refer for inpatient Neurology consultation
  • If seizure occurred in setting of heavy alcohol intake, request Alcohol Counselling service assessment.
  • Consider CDU (EM consultant) or medical admission if alcoholism, poor social circumstances or those without a responsible adult to stay with


  • Confirm neurological recovery, no neuro deficit
  • Record Glucose, U&E (↓Na+)
  • Consider Ca++, Mg++
  • ECG in all cases (troponins if doubt about seizure from collateral Hx); confirm QT interval
  • Please record toxicology screen
  • Please record pregnancy test
  • Admit under on-call medical team


CUH CDU Discharge checklist

  • Check ECG in everyone (you are already doing this)
  • Request MRI and EEG on iCM (phone neurophysiology and EEG will be available that day in most cases)
  • If at the weekend, we have x2 EEG slots at 08:15 each Monday so.... iCM request with patients mobile/contact number
  • Print and provide the EEG patient information sheet with appointment time next Mon @ 08:15
  • Complete CUH First Seizure referral form
  • Warn against driving
  • If a convulsive seizure (particularly if >2 minutes) start Levetiracetam 250mg bid a 1 week, then increase to 500mg bid (Dr D Costello Dec 2012)
  • Give the family a prescription for PRN buccal midazolam 10mg if patient presents with 1st prolonged convulsion (or convincing convulsive collateral Hx)



  • In general, seizures provoked only by alcohol withdrawal, metabolic or drug-related causes, or sleep deprivation should not be treated with antiepileptic drugs
  • Anticonvulsant treatment is indicated only if there is an unacceptable risk of further seizures, which can be determined by 3 factors:
  1. Was event "provoked" or " unprovoked"?
  2. Is EEG normal or does it show (i) focal slowing or (ii) epileptiform discharges. The latter 2 types of EEG findings would predict recurrence
  3. Is imaging normal? Abnormal imaging associated with increased risk of further seizures

Driving and lifestyle advice

  • Driving. Patient should stop driving immediately. They should inform their insurance company (car insurance will be invalid) and GP. A medical report form (D501) will be required before they can return to driving. Some (unprovoked) can resume driving after six months (of seizure free) but will require detailed assessment by a neurologist.
  • Occupation. The patient should inform their employer. In most cases, there will be no impact on work. If their occupation involves driving, working at heights or working with machinery, there may be some restrictions. Please see "Driving".
  • Recreation. Having had a seizure should not stop patients from doing the things they enjoy, although sensible safety precautions do need to be taken. They should be advised not to swim alone, not to lock the bathroom door when bathing, or bathing infants alone.

Content by Dr Íomhar O' Sullivan, Dr Daniel Costello (CUH). Last review 24/03/24.