//CNS// Flashcards
(21 cards)
What is the dosage frequency of anti epileptics determined by?
Plasma half-life
Should be kept as low as possible to encourage adherence
But with large doses, frequency may have to increase to avoid ADRs
Which anti-epileptics have once a day (at bedtime) dosing?
Lamotrigine
Perampanel
Phenobarbital
Phenytoin
What is the frequency of dosing for most antiepileptics when given at their usual dose?
Twice a day
What is epilepsy defined as?
1) at least 2 unprovoked seizures occurring more than 24 hrs apart
2) 1 unprovoked seizure and probability of further seizures similar to the general recurrence risk after 2 unprovoked seizures, ovvuring over the next 10 years
3) diagnosis of an epilepsy syndrome
What is a seizure?
The transient occurrence of signs or symptoms due to abnormal excessive or synchronous neuronal activity in the brain
What is status epilepticus?
Prolonged convulsive seizure for 5 minutes or longer, or recurrent seizures one after the other without recovery in between
What is the prevalence of epilepsy in the Uk?
5-10 cases per 1000
What population group is epilepsy more common in?
People with learning difficulties
What proportion of those with epilepsy have an identified cause?
Cause of epilepsy is only identified in 1/3 of those with the disease
What clinical features indicate TONIC seizure
Short lived , less than 1 min
Abrupt
Generalised muscle stiffening with rapid recovery
What clinical features indicate generalised TONIC CLONIC seizure
Generalised stiffening
Subsequent rhythmic jerking of the limbs
Urinary incontinence
Tongue biting
What clinical features indicate ABSENCE seizure?
Behavioural arrest
Brief sudden lapses of consciousness
More common in children than adults - may look like they are staring blankly into space
What clinical features indicate ATONIC seizure?
Sudden onset of loss of muscle tone
What clinical features indicate MYOCLONIC seizure?
Brief shock like involuntary single or multiple jerks
How to respond if a pt is having a seizure?
- Protect the person from injury - check airaways, recovery position after seizure stops
- If tonic clonic is prolonged or recurrent —> emergency buccaneers midazolam 1st line in community according to pre-arranged protocol
- Emergency admission to hospital if seizures do not respond promptly
How often to epileptics need a review - and what would be addressed during this review?
Once a year
- seizure control, ADRs, compliance, appropriate Rx
- impact of epilepsy on work, education, leisure activities - how to manage risks
- entitlement to drive
- carers’ skills in managing seizures
- contraception - PPP
Which antiepileptics are classed as category 1 by the MHRA and what does this mean?
Phenytoin, carbamazepine, phenobarbital, primidone
—> pt needs to be maintained on a specific manufacturer’s product
What are first-line options for FOCAL seizures?
Carbamazepine
Lamotrigine
What is first-line for generalised TONIC CLONIC seizures?
Sodium valproate unless woman of childbearing potential - in which case lamotrigine
What is first-line for absence seizures?
Ethosuximide
Sodium valproate unless woman of childbearing potential - in which case lamotrigine
Sodium valp should be first line if high risk of generalised tonic clonic
What is first-line for MYOCLONIC seizures?
Sodium valproate unless woman of childbearing potential - in which case topiramate and levetiracetam
