Seizures and Epilepsy

Epilepsy is a condition affecting the brain that makes one more likely to have seizures. A seizure is an episode of transient abnormal electrical brain activity. Most cases (2/3) have an idiopathic cause, but other causes include:

• Brain damage - e.g. Stroke, Trauma, Infection

• Brain tumours

• Embryological defects

• Genetics

There are two main classifications of seizures:

• Focal

• Generalised (Tonic-Clonic, Absence, Atonic, Myoclonic)

Focal

This occurs when the abnormal electrical brain activity starts in a particular region of the brain. The aura experienced before the seizure gives an indication on the location of the seizure:

• Frontal lobe – Motor features

• Parietal lobe – Sensory features

• Temporal lobe – Strange smells, lip smacking, hallucinations

• Occipital lobe – Visual aura

Management

• 1st line – Lamotrigine or Levetiracetam

• 2nd line – Carbamazepine

Generalised

This occurs when the abnormal electrical brain activity starts in both hemispheres of the brain at the same time. There are 4 types of this:

• Tonic-Clonic - LOC, Tonic (stiffening) phase before Clonic (jerking) phase, Tongue biting, Incontinence, Post-ictal phase

  • Patients may experience a temporary weakness/paralysis = Todd’s palsy

  • Management - Sodium Valproate or Lamotrigine/Levetiracetam (if woman of child-bearing age)

• Absence - Patient becomes blank, staring into space and then abruptly returns back to normal - Lasts 10-20 seconds

  • Typically occurs in children, and most stop getting it as they get older

  • Management - Ethosuxamide (1st line)

• Atonic - Sudden loss of muscle tone, whilst retaining consciousness

  • Management - Sodium Valproate or Lamotrigine/Levetiracetam (if woman of child-bearing age)

• Myoclonic - Sudden jerk of a limb, trunk or face

  • Typically occurs in children as part of juvenile myoclonic epilepsy

  • Management - Sodium Valproate or Lamotrigine/Levetiracetam (if woman of child-bearing age)

Investigations

Detailed history! - This is needed to identify the type of seizure through what occurred before, during and after the seizure

N.B. If possible, a collateral history should be taken.

Investigations should be done to look for any provoking causes:

• Examination - May see tongue-biting marks, or soiled clothing

• EEG - Done after 2nd tonic-clonic seizure

• MRI Brain - Look for any structural lesions/pathologies

• Other - ECG, U&Es, BM, Blood/Urine cultures, or LP if evidence of infection

Anti-Epileptic Drugs

• Sodium Valproate - Works by increasing GABA activity, which decreases brain activity

  • It should be avoided in pregnancy as it's teratogenic

  • Other SEs - Weight gain, hair loss, oedema, ataxia, tremor

• Carbamazepine - Benzodiazepine

  • SEs - Agranulocytosis, Aplastic anaemia

DVLA Guidance

The patient MUST CONTACT DVLA!

• One off seizure – Stop and reapply in 6 months

• More than one seizure – Stop and reapply in 1 yr

• Seizure following change in antiepileptic meds – Reapply if seizure was 6+ months ago or you’ve been back on the previous meds for 6 months