Epilepsy Management Flashcards
What is first line for patient with generalised seizures?
Focal seizures? Absence seizures? Myoclonic seizures?
Tonic seizures
Focal - carbamazepine
Generalised - sodium valproate
absence - sodium valproate or ethosuximide
Myoclonic - sodium valproate
Ttonic - sodium valproate or lamotrigine
When are AEDs prescribed? How are they prescribed?
After second seizure
Slowly build up doses over 2-3 months until seizures are controlled or maximum dose is reached
If ineffective or not tolerated, switch no next most appropriate drug
To switch, slowly introduce 2nd drug and withdraw 1st drug when 2nd is established
How are AEDs stopped?
If patient is seizure free for > 2 years and after assessing the risks and benefits
Dose must be decreased slowly over 2-3 months
What must patients who drive be consoled on?
Generally patient cannot drive for 6 months following a seizure
For patients with established epilepsy, they must be fit free for 12 months before being able to drive
What must patients taking other medications be counselled on?
Carbamazepine and phenytoin is a CYP inducer
Sodium valproate is a CYP inhibitor
What must women of childbearing age be counselled on?
Antiepiletics are teratogenic esp. sodium valproate
Take folic acid
Lamotrigine is preferred prior to conception and during pregnancy
Most AEDs are present in breast milk (except carbamazepine and sodium valproate, lamotrigine is thought to be non-harmful)
Effect of oral contraceptive on AED and effect of AED on contraceptive must be considered
- Enzyme inducing AEDs make POP unreliable
- COCP lower lamotrigine levels
What is the MOA/use of sodium valproate carbamazepine lamotrigine phenytoin
Valproate - increases GABA activity
1st line generalised seizure
Carbamazepine - Binds Na channels increasing refractory period
1st line partial seizure
Lamotrigine - Na channel blocker
2nd line
Phenytoin - Binds Na channels increasing refractory period
no longer 1st line due to toxicity (nystagmus, diplopia, tremor, dysarthria, ataxia)
ADRs of sodium valproate
Weight gain and increased appetitie Teratogenix Nausea P450 enzyme inhibitor Ataxia TRemor Hepatitis Pancreatitis Hair loss Thrombocytopenia
ADRs of carbemazepine
P450 inducer Lecuopenia and agranulocytosis Diplopia Blurred vision Impaired balance SIADH
ADRs of Lamotrigine
Maculopapular rash
Steven Johnson syndrome/toxic epidermal necrolysis
- See doctor if rash or flu develop
ADRs of phenytoin
P450 inducer Dizziness ataxia Reduced intellect Depression Gingival hyperplasia Coarse facial features Peripheral neuropathy
What is the management of status epileptics?
Seizure lasting for > 30 minutes or repeated seizure without intervening consciousness
Lorazepam - sow bolus into large vein
Rectal diazepam if IV access is difficult
Buccal midazolam is easier to sue when no IV access
Phenytoin infusion
ICU
Dexamethasone
Generalised tonic clonic?
Sodium valproate
2nd: lamotrigine, carbemazepine
Absence seizures?
Sodium valproate
Ethosuximide
Myoclonic seiczures?
Sodium valproate
2nd: clonazepam, lamotrigine
