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 seizure.

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

 

Types of Seizures

There are many types of seizures. There are different treatments for epilepsy based on the type 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) movements. 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 low.

Management of tonic-clonic seizures is with:

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

 

Focal Seizures

Focal seizures start in the 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 the choice of medication is 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 to 20 seconds. Most patients (more than 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

 

Febrile Convulsions

Febrile convulsions are seizures that occur in children whilst they have a fever. They are not caused by epilepsy or other underlying neurological pathology (such as meningitis or tumours). By definition, febrile convulsions occur only in children between the ages of 6 months and 5 years. Febrile convulsions do not usually cause any lasting damage. One in three will have another febrile convulsion. Having febrile convulsions slightly increases the risk of developing epilepsy in the future.

 

Investigations and Diagnosis

A good history is the key to a diagnosis of epilepsy. It is important to establish that any episodes were seizures, as opposed to vasovagal episodes or febrile convulsions. Try to identify the type of seizure. Patients with a clear history of a febrile convulsion or vasovagal episode do not require further investigations.

An electroencephalogram (EEG) can show typical patterns in different forms of epilepsy and support the diagnosis. Perform an EEG after the second simple tonic-clonic seizure. Children are allowed one simple seizure before being investigated for epilepsy.

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. It should be considered when:

  • The first seizure is in children under 2 years
  • Focal seizures
  • There is no response to first line anti-epileptic medications

Additional investigations can be considered to exclude other pathology that may cause seizures:

  • ECG to exclude problems in the heart.
  • Blood electrolytes including sodium, potassium, calcium and magnesium
  • Blood glucose for hypoglycaemia and diabetes
  • Blood cultures, urine cultures and lumbar puncture where sepsis, encephalitis or meningitis is suspected

 

General Advice

Patients and families presenting with seizures need to be given advice about safety precautions, recognising, managing and reporting further seizures. It is important to avoid situations where a seizure may put the child in danger, with advise to:

  • Take showers rather than baths
  • Be very cautious with swimming unless seizures are well controlled and they are closely supervised
  • Be cautious with heights
  • Be cautious with traffic
  • Be cautious with any heavy, hot or electrical equipment

Older teenagers with epilepsy will need to avoid driving unless they meet specific criteria regarding control of their epilepsy. These rules change frequently so it is always worth looking them up if advising patients.

 

Anti-Epileptic Drugs

There are a number of maintenance anti-epileptic drugs that work by raising the seizure threshold and reducing the likelihood of the patient having a seizure. These will be initiated, monitored and titrated by a paediatric specialist with expertise in epilepsy.

 

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 of sodium valproate include:

  • 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 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

 

Management of Seizures

  • Put the patient in a safe position (e.g. on a carpeted floor)
  • Place in the recovery position if possible
  • Put something soft under their head to protect against head injury
  • Remove obstacles that could lead to injury
  • Make a note of the time at the start and end of the seizure
  • Call an ambulance if lasting more than 5 minutes or this is their first seizure.

 

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, repeated after 10 minutes if the seizure continues

If the seizures persist the final step is an infusion of IV phenobarbital or phenytoin. At this point intubation and ventilation to secure the airway needs to be considered, along with transfer to the intensive care unit if appropriate.

 

Medical options in the community:

  • Buccal midazolam
  • Rectal diazepam

 

Last updated January 2020
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