Epilepsy

Question 1

Seizure definition

Answer 1

uncontrolled electrical discharge in brain

Question 2

3 focal (localised) seizure types

Answer 2

1. aware: preserved consciousness, symptoms of involuntary repetitive movement
2. Impaired awareness: altered consciousness, symptoms include confusion + memory loss after
3. Focal to bilateral tonic-clonic: loss of consciousness, preceded by aura
   -> tonic clonic meaning contraction + rhythmical movements

Question 3

Describe the 4 aura sensations

Answer 3

• sensory: numbness, tingling
• motor: jerky limb, twitchy face
• autonomic: increased HR, nausea
• psychic: deja vu, fear

Question 4

Contrast glutamate + GABA in neurotransmission

Answer 4

Glutamate = increases nerve depolarisation - activates NMDA channels

GABA = inhibits impulses via causing membrane hyperpolarisation -> K+ + Cl- influx

Question 5

3 general seizure types

Answer 5

1. tonic-clonic - loss of consciousness, body stiff then jerky
2. Myoclonic - consciousness X impaired, brief muscle contraction
3. absence - loss of consciousness, blank stare

Question 6

when is something classified as epilepsy

Answer 6

2 unprovoked seizures > 24 hours apart

Question 7

3 drugs that enhance Na+ channel mediated inhibition + MOA

Answer 7

Phenytoin
Carbamazepine
Lamotrigine

• enhances Na+ channel mediation by acting directly on Na+ channels
  -> slows recovery from inactivated state therefore prevents rapid firing

Question 8

Carbamazepine indications

Answer 8

• simple + complex focal seizures
• generalised tonic-clonic seizures

Question 9

Phenytoin + lamotrigine indications

Answer 9

focal seizures
generalised tonic-clonic seizures

Question 10

Valproate MOA + indications

Answer 10

• absence
• tonic clonic
• myoclonic
• focal

-> prolongs Na channel inactivation
-> inhibits T-type Ca channels
therefore enhances GABA effects

Question 11

Valproate adverse reactions

Answer 11

• weight gain
• tremors

Avoid starting in females of childbearing potential b/c causes defects

Question 12

Topiramate indications, MOA + adverse effects

Answer 12

• focal / generalised tonic clonic
• block Na channels + AMPA receptor
• inhibit Ca2+ channels
  therefore enhance GABA effects
• fatigues + weight loss

Question 13

Levetiracetam indications, MOA + adverse effects

Answer 13

• focal/generalised seizures
• modulate neurotransmission
• anxiousness, drowsiness, insomnia

Question 14

Epilepsy in women + pregnancy

Answer 14

• may decrease effectiveness of contraceptives
• can cause spina bifida + cleft palate
  -> all anti-epileptic medication may be teratogenic