PHAR: Drug Treatment of Seizure Disorders 1 & 2

Question 1

What is the proper ILAE classification of seizures?

Answer 1

• Focal/partial
  
  • simple partial
    
    • preservation of normal consciousness
  • complex partial
    
    • alteration of consciousness (30sec - 3min)
  • secondarily generalized
    
    • grand mal
• Generalized
  
  • Absence
    
    • blank spell
    • sudden onset
  • Tonic-clonic
    
    • grand mal
  • Myoclonic
    
    • like when you’re falling asleep or hiccup
  • Tonic/Atonic

Question 2

What are general counselling and education things after suspected seizure?

Answer 2

• No showers
• No swimming/fishing alone
• No working at height
• NO DRIVING

Question 3

When should antiepileptic drug treatment be started?

Answer 3

• Acute symptomatic seizures (short term only) - YES
• Recurrent unproboked seizures (=Epilepsy) - YES
• After a first-ever unprovoked seizure? - NOT USUALLY
  
  • unless high recurrence risk - e.g. old person
  • individual REALLY wants it

Question 4

What is the prognosis of epilepsy?

Answer 4

• 70% control of seizures and remission
• 20% regular medicine, ± breakthrough seizures
• 10% poorly controlled

Question 5

What factors help us select an anti-epileptic drug?

Answer 5

• Determined mainly by seizure types
• Effectiveness and side effects of available drugs
• Indvidual patient circumstances (age, sex, other issues)

First try monotherapy, then multiple medicines if several monotherapy trials fail.

Question 6

Routine AED blood level monitoring is not indicated.

When would you use blood level monitoring?

Answer 6

• suspected poor compliance
• suspected toxicity where more than one drug may be responsible
• adjustment of phenytoin dose

Question 7

What are the first line AED medicines?

Answer 7

Generalised-onset epilepsies:

• Valproate - male, children
• Lamotrigine - women (not myoclonus)
• Ethosuximide - absence only
• Carbamazepine - if tonic-clonic seizures alone

Partial and secondary generalised epilepsy:

• Carbamazepine
• Valproate

Question 8

When would you use valproate and carbamazepine?

Answer 8

Valproate - all seizure types, but major teratogen

Carbamazepine - partial and tonic-clonic seizures, slow introduction

Question 9

What are side effects of carbamazepine to look out for?

Answer 9

• Stevens Johnson syndrome (especially Han chinese) - look out for rash and stop immediately

Question 10

Explain the use of phenytoin as an AED?

Answer 10

• Partial and tonic-clonic seizures
• Still number 3 in australia
• Very powerful
• Easy introduction
• Non-linear kinetics (needs care)
• Don’t give intramuscularly

Question 11

What are reasons for treatment failure?

Answer 11

1. Patient factors (50%) - poor compliance, interactions with other treatments, precipitating factors
2. Wrong diagnosis - not seizures - syncope, pseudoseizure, sleep disorders
3. Wrong medicine for type of epilepsy
4. Underlying condition - progressive condition

Question 12

Why are benzodiazepines used in epilepsy?

Answer 12

• All seizure types
• Clobazam is oral, well tolerated, and used for temporary treatment for seizure clusters
• Midazolam is iv/intransal - rapidly absorbed to switch off seizures
• Clobazam is not on PBS

Question 13

Explain treatment of status epilepticus - convulsive

Answer 13

1. Observe (video recording) - tonic-clonic normally self-limiting
2. If ongoing - stop with a benzodiazepine
3. Prevent seizures and allow breathing to continue unassisted with phenytoin

Question 14

What is the most commonly prescribed AED in the world?

Answer 14

Phenobarb - highly effective all types

Question 15

When should treatment be stopped?

Answer 15

After minimum 2 years seizure free