Epilepsy

Question 1

Epilepsy

Answer 1

Epilepsy is a common neurological condition characterised by recurrent seizures.

It should be remembered that epilepsy is not the only reason people have seizures

Question 2

Other than epilepsy; what are the other causes of seizures?

Answer 2

Insult to the brain, infection, trauma or metabolic disturbance, tumors

Question 3

Febrile convulsions

Answer 3

Typically occur in children between the ages of 6 months and 5 years
Usually occur early in a viral infection as the temperature rises rapidly
Seizures are typically brief and generalised tonic/tonic-clonic in nature

Question 4

What age do febrile convulsions usually occur?

Answer 4

Typically occur in children between the ages of 6 months and 5 years

Question 5

Alcohol withdrawal seizures

Answer 5

Occur in patients with a history of alcohol excess who suddenly stop drinking, for example following admission to hospital

Question 6

When do alcohol withdrawal seizures occur after stopping alcohol?

Answer 6

36 hours following cessation of drinking

Question 7

What can be done to prevent alcohol withdrawal seizures in hospitals?

Answer 7

given benzodiazepines following cessation of drinking to reduce the risk

Question 8

Psychogenic non-epileptic seizures

Answer 8

Previously termed pseudo seizures, describes patients who present with epileptic-like seizures but do not have characteristic electrical discharges.

Patients may have a history of mental health problems or a personality disorder

Question 9

Partial focal seizures can be describes as either simple or complex; what is the difference between the two?

Answer 9

a. Simple: without impaired consciousness

b. Complex: with impaired consciousness

Question 10

What are focal seizures?

Answer 10

Previously termed partial seizures

These start in a specific area, on one side of the brain

Question 11

What are the six types of generalized seizures?

Answer 11

o	tonic-clonic (grand mal)
o	tonic
o	clonic
o	typical absence (petit mal)
o	myoclonic: brief, rapid muscle jerks
o	atonic

Question 12

What are generalized seizures?

Answer 12

These engage or involve networks on both sides of the brain at the onset

Consciousness lost immediately.

Question 13

How are generalized and focal/partial seizures differentiated?

Answer 13

Consciousness lost immediately in generalized, in partial consciousness may or may not be lost

Question 14

What investigations are done following the first seizure in a patient?

Answer 14

Following their first seizure patients generally have both an electroencephalogram (EEG) and neuroimaging (usually an MRI).

Question 15

When are epileptics drugs started in epileptic seizures?

Answer 15

Most neurologists now start antiepileptics following a second epileptic seizure.

Question 16

What is the first line drug in generalized seizures?

Answer 16

sodium valproate

Question 17

What is the first line drug in focal seizures?

Answer 17

carbamazepine

Question 18

When can patients drive following a seizure for the first time?

Answer 18

Cannot drive for 6 months following a seizure.

Question 19

When can patients with established epilepsy drive?

Answer 19

For patients with established epilepsy they must be fit free for 12 months before being able to drive

Question 20

What epilepsy medications are tetratogenic?

Answer 20

antiepileptics are generally teratogenic, particularly sodium valproate.

Question 21

What is the mechanism of action of sodium valproate?

Answer 21

Increases GABA activity

Although the mechanism of action remains to be elucidated, valproate sodium increases concentrations of gamma-aminobutyric acid (GABA) in the brain, probably due to inhibition of the enzymes responsible for the catabolism of GABA.

Question 22

Side effects of sodium valproate

Answer 22

increased appetite and weight gain
alopecia: regrowth may be curly
P450 enzyme inhibitor
ataxia
tremor
hepatitis
pancreatitis
thrombocytopaenia
teratogenic (neural tube defects)

Question 23

Side effects of Carbamazepine

Answer 23

1. P450 enzyme inducer
2. dizziness and ataxia
3. drowsiness
4. leukopenia and agranulocytosis
5. syndrome of inappropriate ADH secretion
6. visual disturbances (especially diplopia)

Question 24

Mechanism of action of Carbamazepine

Answer 24

Binds to sodium channels increasing their refractory period

Question 25

Mechanism of action of Lamotrigine

Answer 25

Sodium channel blocker

Question 26

Side effects of Lamotrigine

Answer 26

Stevens-Johnson syndrome - The syndrome often begins with flu-like symptoms, followed by a red or purple rash that spreads and forms blisters. The affected skin eventually dies and peels off.

Stevens-Johnson syndrome is a medical emergency that requires treatment in hospital, often in intensive care or a burns unit.

Question 27

When is Lamotrigine used in epilepsy?

Answer 27

Used second line for a variety of generalised and focal seizures

Question 28

Side effects of Phenytoin

Answer 28

P450 enzyme inducer
dizziness and ataxia
drowsiness
gingival hyperplasia, hirsutism, coarsening of facial features
megaloblastic anaemia
peripheral neuropathy
enhanced vitamin D metabolism causing osteomalacia
lymphadenopathy

Question 29

Mechanism of action of phenytoin

Answer 29

Binds to sodium channels increasing their refractory period

Question 30

In the pre-hospital setting, an epilepsy seizure of more than 5-10 mins should be given rescue medication - what is this?

Answer 30

Benzodiazepines such as diazepam are typically used may be administered rectally or intranasally/under the tongue.

Question 31

Patients with epileptic seizure of more than 10 mins not stopping despite benzodiazepines are referred to as what?

Answer 31

Status epilepticus.

This is a medical emergency requiring hospital treatment.

Question 32

What is status epilepticus?

Answer 32

a single seizure lasting >5 minutes, or

>= 2 seizures within a 5-minute period without the person returning to normal between them

Question 33

When patient has refractory status (seizure lasting for up to 45 minutes or more); what management is done?

Answer 33

General anesthesia

Question 34

What are absence seizure features?

Answer 34

• absences last a few seconds and are associated with a quick recovery
• seizures may be provoked by hyperventilation or stress
• the child is usually unaware of the seizure
• they may occur many times a day
• EEG: bilateral, symmetrical 3Hz spike and wave pattern

Question 35

Why is sodium valproate considered tetragenic?

Answer 35

Causes neural tube defects