PHARM - Antiepileptic Drugs - Week 10

Question 1

What percentage of the worlds population has epilepsy?

Answer 1

1%

Question 2

What percentage of those with epilepsy have seizures?

Answer 2

8%

Question 3

Is there a genetic link to epilepsy?

Answer 3

Yesd

Question 4

Name 7 possible causes of epilepsy.

Answer 4

Fever
Brain tumour
Trauma
Abnormalities in CNS development
Infection
Stroke
Heredity

Question 5

Name 7 precipitating factors for epilepsy.

Answer 5

Stress/anxiety
Sleep deprivation/fatigue
Hormonal changes associated with the menstrual cycle
Certain medications
Diabetes/blood sugar imbalances
Neon/xeon strobe flashes
Rapid motion

Question 6

How can seizures be measured? What are they characterised by (2)?

Answer 6

Using electroencephalography - it has a sudden onset and is characterised by hyper-excitability and hyper-synchronised activity of large groups of neurons

Question 7

What are epilepsy recurrent seizures due to?

Answer 7

Chronic underlying process

Question 8

Name the two broad classifications of seizures and list two subtypes each.

Answer 8

Focal (partial)
-simple
-complex

Generalised
-tonic-clonic
-absence

Question 9

Where do complex focal seizures arise from?

Answer 9

Temporal lobe

Question 10

Is there a loss of consciousness in simple focal seizures?

Answer 10

No

Question 11

List 4 broad treatment options for epilepsy and describe them if appropriate ().

Answer 11

Identify the underlying cause
Avoid precipitants (behavioural modification)
Anti-epileptic drugs
-palliative rather than curative
Surgery

Question 12

What is the most common surgical approach to epilepsy?

Answer 12

Temporal lobe resection

Question 13

Consider anti-epileptic drugs. Do patients respond well to a single drug?

Answer 13

33% do not respond to a single epileptic - polytherapy needed

Question 14

What is the aim of antiepileptic drugs?

Answer 14

To inhibit abnormal neuronal discharge rather than correct the underlying cause

Question 15

Can a synapse be both inhibitory and excitatory?

Answer 15

Yes, it can be one, the other, or both

Question 16

Can a neurotransmitter be both excitatory and inhibitory?

Answer 16

Yesd like serotonin

Question 17

What are two ways an anti-epileptic drug can work?

Answer 17

Reduce excitatory input
Enhance inhibitory input

Question 18

Briefly describe how phenytoin works.

Answer 18

Limits excitatory nerve activation by blocking Na+ channels

Question 19

List 3 mechanisms of action that an anti-epileptic drug can have.

Answer 19

Inhibit voltage-dependent Na+ channels
Inhibit voltage-dependent Ca2+ channels
Enhance GABA action

Question 20

What channels are active in absence seizures? What Hz spike is seen in these seizures on an EEG?

Answer 20

T-type Ca2+ channels are active
Has a characteristic 3Hz spike ans wake pattern

Question 21

What are three ways GABA action can be enhanced?

Answer 21

Allosteric modulation on the GABAa receptor
Inhibiting reuptake
Inhibit GABA transaminase

Question 22

List 5 side effects of anti-epileptic drugs.

Answer 22

Sedation
Unsteadiness
Diplopia
Nausea
Increased fracture risk

Question 23

What is very important during epilepsy therapy?

Answer 23

Patient compliance