What is epilepsy?
Epilepsy is an umbrella term for a condition where there is a tendency to have seizures
What is a seizure?
Seizures are transient episodes of abnormal electrical activity in the brain
Investigation used in Epilepsy
- An EEG (electroencephalogram) can show typical patterns in different forms of epilepsy and support the diagnosis
- An MRI brain to diagnosis structural problems that may be associated with seizures and other pathology such as tumours
Types of seizures
- Generalised tonic clinic seizures
- Focal seizures
- Absence seizures
- Atonic seizures
- Myoclonic seizures
- Infantile spasms
Describe the features of a generalised tonic clonic seizure
There is loss of conciousness 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.
There is a prolonged post-ictal period.
Management of tonic clonic seizures is with:
- First line: sodium valproate
- Second line: lamotrigine or carbamazepine
Describe the features of 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
Management of focal seizures
- First line: carbamazepine or lamotrigine
- Second line: sodium valproate or levetiracetam
Describe the features of abscence seizures
Absence seizure typically happen in children. The patient becomes blank, stares into space and then abruptly returns to normal. These typically last 10-20 seconds. Most patients (>90%) stop having absence seizures as they get older.
Management of absence seizures
Sodium valproate or ethosuximide
Describe the features of an atonic seizure
Also known as drop attacks
- brief lapses in muscle tone
- don’t usually last more than 3 minutes
- they typically begin in childhood
- usually remain conscious
Management of atonic seizures
- First line: sodium valproate
- Second line: lamotrigine
Describe the features of myoclinic seizures
Present as sudden brief muscle contractions, like a sudden “jump”. The patient usually remains awake during the episode.
Myoclinic seizures management
- First line: sodium valproate
- Second line: lamotrigine, levetiracetam or topiramate
Describe the features of infantile spasms
Also known as West syndrome
- Starts in infancy at around 6 months old
- Characterised by clusters of full body spasms
- Poor prognosis: 1/3 die by the age of 25, however 1/3 are seizure free
What is sodium valproate used for?
How does it work?
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.
Side effects of sodium valproate?
- Teratogenic so patients need careful advice about contraception
- Liver damage and hepatitis
- Hair loss
- Tremor
What is Carbamazepine used for?
Notable side effects
First line for focal seizures
Side effects:
- Agranulocytosis
- Aplastic anaemia
- Induces the P450 system so there are many drug interactions
Phenytoin side effects
- Folate and vitamin D deficiency
- Megaloblastic anaemia (folate deficiency)
- Osteomalacia (vitamin D deficiency)
Ethosuximide side effects
- Night terrors
- Rashes
Lamotrigine side effects
- Steven-Johnson syndrome or DRESS syndrome (life threatening skin rashes)
- Leukopenia
