Epilepsy Flashcards
(28 cards)
Epilepsy Control
- Treatment aims to prevent occurrence of seizures
- Adjust doses if necessary. We want to start with small doses and gradually increase the dose until the seizures are controlled
-choice of epileptic drug is determined by several factors - including co morbidity,concomitant medication, age and sex and epilepsy syndrome, - keep dose and frequency as low as possible to encourage patient adherence
Anti epileptics frequency of doses
-Most antieplieptic drugs can be given twice a day
- some of them have a long half and can be given Once daily at bedtime
Once daily anti epileptics (LP3 - Long period)
- Lamotrigine
- Perampanel
- Phenobarbital
- Phenytoin
Management of epilepsy
- Monotherapy with 1st line antiepileptics
- If this fails, then give monotherapy with a second drug
- Cautiously change from one anti-epileptic drug to another
-slowly withdraw first drug only when the new reg has been established - avoid abrupt withdrawal - this may cause rebound seizures
- combination therapy with 2 or more antiepileptics may be necessary - but does increase the chances of sidde effects and other drug interactions
What is advice if it fails to control seizures?
- if combo therapy is not successful- then just revert to the regimen (either monotherapy or combo therapy) Which provided the best kind of balance between tolerance and and efficacy
What is the MHRA advice?
- There is potential harm when switching patients that are stabilised on certain brands for epilepsy to generic products
- antiepileptics are divided into 3 groups or risk categories to help healthcare professionals decide if continuity is essential or not
Category 1
Maintain patients on specific brands( only when being treated for epilepsy and not another condition) - eg, Carbamazepine that is prescribed for bipolar does not have to be on the same brand where as tegrotol for epilepsy does.
Report any sideffects suspected via yellow card scheme for any anti epileptic drugs
Switching between formulations
Switching between formulations can be dangerous - different formulations have different bioav. Therefore, might not meet the threshold for epileptic patients. Different brands can also be different
Which drugs by brand? Ie. Cat 1 CPR3
-Carbamazepine (Tegrotol, Carbagen)
- Phenytoin
- Phenobarbital
- Primidone
ALL of the above can also cause hypersensitivity
Category 2
- Need for continuity depends on clinical judgment and consultation with patients and carers
Which anti epileptics are category 2? ICCTV
Lamotrigine
Topiramate
Valproate
Clobazam
Clonazepam
Category 3
- no need for specific brand in terms of clinical value
Category 3 anti-epileptics?
- levetiracetam
-Gabapentin
-pregabalin - Vigabatrine
- Ethosuzimide
-Tigabine
-Brivacetam
ANTI-EPILEPTIC Hypersensitivity syndrome?
- Rare but potentially fatal syndrome associated with antiepileptics drugs (CPPPr3+ Lamotrigine and lacosamide)
- symptoms start between 1-8 weeks of exposure (monitor first 2 months)
- most common symptoms are fever,rash,liver dysfunction,renal and pulmonary abnormalities and multi- organ failure)
- what to do? Stop immediately and refer patient to GP if any of the above symptoms occur
MHRA WARNING FOR SUICIDE
RISK OF SUICIDE - when taking anti epileptics - small increased risk of suicidal thoughts and behaviours
- symptoms can occur 1 week after starting the medication
- patients and carers need to be aware of the risk - should seek medical advice if there are any mood changes,distressing thoughts, feelings of suicide or self harm
- NB - watch out for suicidal thoughts and hypersensitivity in the first few months of starting an antiepileptic drug
What are the key interactions
Interactions between antiepileptics are complex and may increase toxicity without increasing antiepileptic effect
Normally, enzyme inhibition or induction interactions
The withdrawal of antiepileptics
- withdraw under a specialist only!!
- don’t withdraw abruptly, can precipitate severe rebound seizures especially benzodiazepines and barbiturates
- reduce the dose gradually (barbiturates may take months)
- withdraw only one drug at a time for patients on multiple drugs
- withdraw drugs gradually over 2-3 months by reducing the daily dose by 10-25% at intervals of 1-2 weeks
- Benzodiazipines may need to be withdrawn over 6 months or longer
Driving Advice for epileptic patients
- if a driver has a seizure of any type, no known cause then they need to inform the dvla
- Patients with a first unprovoked epileptic seizure and no known cause or a single isolated seizure need to stop driving for 6 months
- patients that have establish epilepsy may drive, provided that they are not a danger to the public and compliant with treatment and follow up
- to continue driving, patients mist be seizure free for at least 1 year - they must not have a history of unprovoked seizures
Driving with medication Change or withdrawal:
- patients should not drive during medication changes or withdrawal of antiepileptic drugs and for 6 months after their last dose
- if a seizure occurs due to a change or withdrawal or antieplieptic drugs, their drivers license is revoked for a year
Wait for 6 months to drive if…
-1st unprovoked/single isolated seizure
- Had a possible dose change
Wait for 1 year if
Have had a seizure due to drug change or withdrawal
STOP DRIVING IMMEDIATELY IF..
Have had any seizures of any type
Epilepsy and Pregnancy - what is the main thing to remember about the drugs?
- There is a massive increased risk of teratogenicity with antiepileptic drugs, especially during the 1st trimester and particularly if the patient takes 2 or more antiepileptic drugs
Which anti- epileptic has the highest risk in pregnancy?
Valporate associated with the highest risk of very serious developmental issues - up to a 30-40% risk and congenital malformations
- Valporate must not be used in females of child bearing potential unless conditions of the PPP are met and there is no clear alternative that is present
