Anti-epileptic drugs

Question 1

MOA of topiramate + uses (2)

Answer 1

Increases GABA activation

adjunct medication for generalised seizures, and stand alone therapy for partial seizures.

prophylaxis treatment for migraine

Question 2

Side effects of topiramate

Answer 2

Affects the nervous system;

ataxia, dizziness, drowiness, nystagmus, paresthesia, and psychomotor impairment.

Note: pregnancy category D - risk of cleft palate, therefore women need contraception control.

Question 3

MOA of Gabapentin

Answer 3

increases release of GABA from central neurones

NB. has a relatively short half-life, therefore needs to be given frequently.

Question 4

What are the notable s/e of gabapentin?

Answer 4

drowsiness

extrapyramidal effects; tremor, ataxia, dizziness, nystagmus

Note: antiacids decrease serum levels

Question 5

What is Gabapentin used for?

Answer 5

continuous, burning neuropathic pain

eg. trigeminal neuralgia, postherpetic neuralgia.

NB Try amittriptyline first

Question 6

What drugs can be used to treat fibromyalgia?

Answer 6

1. Pregabalin was one of the first drugs indicated for this.
2. Duloxetine (SNRI)
3. Tramadol