Epilepsy

Epilepsy is an umbrella term for a condition where there is a tendency to have seizures. Seizures are transient episodes of abnormal electrical activity in the brain. There are many different types of seizures.

A diagnosis of epilepsy is made by a specialist based on the characteristics of the seizure episodes.

 

Investigations

An electroencephalogram (EEG) can show typical patterns in different forms of epilepsy and support the diagnosis.

An MRI brain can be used to visualise the structure of the brain. It is used to diagnose structural problems that may be associated with seizures and other pathology such as tumours.

Other investigations can be used to exclude other pathology, particularly an ECG to exclude problems in the heart.

Types of Seizures

There are many types of seizures. There are different first line treatments for epilepsy with different types of seizures. The aim of treatment is to be seizure free on the minimum anti-epileptic medications. Ideally they should be on monotherapy with a single anti-epileptic drug. Treatment is initiated and guided by a specialist.

 

Generalised Tonic-Clonic Seizures

These are what most people think of with an epileptic seizure. There is loss of consciousness and tonic (muscle tensing) and clonic (muscle jerking) episodes. Typically the tonic phase comes before the clonic phase. There may be associated tongue biting, incontinence, groaning and irregular breathing.

After the seizure there is a prolonged post-ictal period where the person is confused, drowsy and feels irritable or depressed.

Management of tonic-clonic seizures is with:

  • First line: sodium valproate
  • Second line: lamotrigine or carbamazepine

 

Focal Seizures

Focal seizures start in temporal lobes. They affect hearing, speech, memory and emotions. There are various ways that focal seizures can present:

  • Hallucinations
  • Memory flashbacks
  • Déjà vu
  • Doing strange things on autopilot

One way to remember the treatment is that they are the reverse of tonic-clonic seizures:

  • First line: carbamazepine or lamotrigine
  • Second line: sodium valproate or levetiracetam

 

Absence Seizures

Absence seizures typically happen in children. The patient becomes blank, stares into space and then abruptly returns to normal. During the episode they are unaware of their surroundings and won’t respond. These typically only lasts 10-20 seconds. Most patients (> 90%) stop having absence seizures as they get older. Management is:

  • First line: sodium valproate or ethosuximide

 

Atonic Seizures

Atonic seizures are also known as “drop attacks”. They are characterised by brief lapses in muscle tone. These don’t usually last more than 3 minutes. They typically begin in childhood. They may be indicative of Lennox-Gastaut syndrome. Management is:

  • First line: sodium valproate
  • Second line: lamotrigine

 

Myoclonic Seizures

Myoclonic seizures present as sudden brief muscle contractions, like a sudden “jump”. The patient usually remains awake during the episode. They occur in various forms of epilepsy but typically happen in children as part of juvenile myoclonic epilepsy. Management is:

  • First line: sodium valproate
  • Other options: lamotrigine, levetiracetam or topiramate

 

Infantile spasms

This is also known as West syndrome. It is a rare (1 in 4000) disorder starting in infancy at around 6 months of age. It is characterised by clusters of full body spasms. There is a poor prognosis: 1/3 die by age 25, however 1/3 are seizure free. It can be difficult to treat but first line treatments are:

  • Prednisolone
  • Vigabatrin

 

Epilepsy Maintenance Medication

Sodium Valproate

This is a first line option for most forms of epilepsy (except focal seizures). It works by increasing the activity of GABA, which has a relaxing effect on the brain. Notable side effects:

  • Teratogenic so patients need careful advice about contraception
  • Liver damage and hepatitis
  • Hair loss
  • Tremor

 

There are a lot of warning about the teratogenic effects of sodium valproate and NICE updated their guidelines in 2018 to reflect this. It must be avoided in girls or women unless there are no suitable alternatives and strict criteria are met to ensure they do not get pregnant.

 

Carbamazepine

This is first line for focal seizures. Notable side effects are:

  • Agranulocytosis
  • Aplastic anaemia
  • Induces the P450 system so there are many drug interactions

 

Phenytoin

Notable side effects:

  • Folate and vitamin D deficiency
  • Megaloblastic anaemia (folate deficiency)
  • Osteomalacia (vitamin D deficiency)

 

Ethosuximide

Notable side effects:

  • Night terrors
  • Rashes

 

Lamotrigine

Notable side effects:

  • Stevens-Johnson syndrome or DRESS syndrome. These are life threatening skin rashes.
  • Leukopenia

 

Status Epilepticus

Status epilepticus is an important condition you need to be aware of and how to treat. It is a medical emergency. It is defined as seizures lasting more than 5 minutes or more than 3 seizures in one hour.

 

Management of status epileptics in the hospital:

Take an ABCDE approach:

  • Secure the airway
  • Give high-concentration oxygen
  • Assess cardiac and respiratory function
  • Check blood glucose levels
  • Gain intravenous access (insert a cannula)
  • IV lorazepam 4mg, repeated after 10 minutes if the seizure continues
  • If seizures persist: IV phenobarbital or phenytoin

 

Medical options in the community:

  • Buccal midazolam
  • Rectal diazepam

 

Last updated April 2019
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