Epilepsy treatment

Question 1

basic mechanism

Answer 1

excess excitation - glutamate

insufficient inhibition - GABA

Question 2

phenytoin

Answer 2

mechanism:

adverse effects:

Question 3

ethosuxamide

Answer 3

children with absence seizures

Question 4

Na valproate

Answer 4

caution in women of childbearing age - spina bifida, lower IQ
for any generalised epilepsy
general rule - use if unsure

weight gain, parkinsonism

Question 5

NICE

Answer 5

avoid: carbamazepine

Question 6

lamotrigine

Answer 6

partial seizure under certain circumstances

if used as monotherapy start 25mg/d up to max. hjalve doses if used with sodium valproate, double if on phenytoin or carbamazepine

Question 7

levetiracetam

Answer 7

tiredness, dizziness, aggression

safe to use in pregnancy, any adverse effects are as yet unknown
try and use as few drugs as possible to reduce teratogenicity

Question 8

carbamazepine

Answer 8

partial and focal seizures

initial dose 100mg/12h, increase by 200mg/d every 2 weeks up to a max of 1000mg/12h
SE: leucopenia, diplopia, blurred vision, impaired balance, drowsiness, mild generalised rash, SIADH (rare)

Question 9

side effects

Answer 9

skin rash (hypersensitivity)
ataxic gait
tremor
teratogenicity - spina bifida
wieght gain
behavioural disturbance
also beware drug interactions

Question 10

starting meds

Answer 10

start low and slowly increase until Sx free
if seizures fail to respond, reconsider diagnosis
add new first line drug and gradually reduce 2nd drug until Sx control optimal

Question 11

protein binding

Answer 11

many of these drugs are protein bound

albumin levels will then have an effect on toxicity

Question 12

protein binding

Answer 12

many of these drugs are protein bound

albumin levels will then have an effect on toxicity

Question 13

efficacy

Answer 13

47% seizure free in 1st AED

14% seizure free on 2nd or 3rd AED

Question 14

efficacy

Answer 14

47% seizure free in 1st AED
14% seizure free on 2nd or 3rd AED
if not reassess diagnosis, consider surgery, and vagal nerve stimulation

Question 15

efficacy

Answer 15

47% seizure free in 1st AED
14% seizure free on 2nd or 3rd AED
if not reassess diagnosis, consider surgery, and vagal nerve stimulation

Question 16

status epilepticus

Answer 16

ABC
high flow O2
IV lorazepam or diazepam (buccal/rectal)
if no response, use phenytoin (watch for hypotension, arrhythmias)
if still uncontrolled seek further help, ICU, propofol, thiopentone

Question 17

generalised tonic-clonic seizures

Answer 17

sodium valproate or lamotrigine (often better tolerated, less teratogenic) 1st line
then carbamazepine or topiramate

Question 18

absence seizures

Answer 18

sodium valproate, lamotrigine or ethosuximide

Question 19

tonic, atonic, myoclonic seizures

Answer 19

as for generalised:
sodium valproate or lamotrigine (often better tolerated, less teratogenic) 1st line
but AVOID carbamazepine, which may worsen seizures

Question 20

partial seizures (+/- secondary generalization)

Answer 20

carbamazepine 1st line

then sodium valproate, lamotrigine

Question 21

status epilepticus

Answer 21

open and maintain airway
recovery position
insert oral/nasal airway, intubate if necessary

high flow O2 and, if required, suction

IV access, take blood (U&E, LFT, FBC, BM, Ca2+)

slow IV bolus phase - to stop seizures:
eg lorazepam, 2-4mg. give second dose if no reaction in 10mins

thiamine 250mg IV over 30min if alcoholism/malnourishment suspected (and glucose, unless known to be normal)

correct hypotension with IV fluids

IV infusion phase:
phenytoin 15-20mg/kg IVI or diazepam infusion
monitor ECG and BP

general anaesthesia phase:
continuing seizures require specialist help with paralysis and ventilation