CARBAMEZEPINE

Question 1

Drug class

Answer 1

anti-convulsant

Question 2

How does it work? (4)

Answer 2

1. inhibits neuronal sodium channels
2. inhibits the spread of seizure activity
   - in epilepsy
3. blocks synaptic transmission
   - in the trigemimal nucleus
4. reduces electrical kindling in the temporal lobe and limbic system
   - this stabilises mood in bipolar disease

Question 3

Indications (3)

Answer 3

1. bipolar
2. epilepsy
3. trigeminal neuralgia

Question 4

Contra-indications (4)

Answer 4

1. in utero
   - neural tube defects
2. pregnancy in epileptics
3. anti-epileptic hypersensitivity syndrome
4. hepatic, renal or cardiac disease
   - toxicity

Question 5

Side effects (9)

Answer 5

1. GI upset
2. neurological effects

• dizziness
• ataxia (lack of muscle coordination)

3. hypersensitivity
4. anti-epileptic hypersensitivity syndrome
5. skin reactions
   - Steven Johnson’s
6. fever
7. lymphadenopathy
8. oedema
   - anti-diuretic effect
9. hyponaetremia
   - anti-diuretic effect

Question 6

Interactions (3)

Answer 6

1. drugs metabolised by cytochrome P450

• induces this enzyme
• reduces efficacy of these drugs

e. g. warfarin, progesterone and oestrogen
2. cytochrome P450 inhibitors
- increases concentration and adverse effects
e. g. macrolides
3. anti-epileptic drugs
- reduces efficacy

Question 7

Elimination

Answer 7

1. urine