Loading....
Coupon Accepted Successfully!

Pharmacology

Open Flashcards

CNS Part-1

Question
8 out of 58
 

Which antiepileptic does not act via sodium channel blockade? (DNB Dec 2011)



A Vigabatrin
B Carbamazepine

C Lamotrigine
D Phenytoin

Ans. A Vigabatrin

Vigabatrin (γ vinyl GABA. - is all inhibitor of GABA-transaminase, hence es breakdown of GABA and es it's concentration in synaptic cleft.

  1. Useful in refractory epilepsy especially partial seizures with/ without generalization
  2. S/E: Behavior changes, depression, psychosis.
  3. Carbamazepine: Prolongation of sodium channel inactivation
  4. Lamotrigine: Prolongation of sodium channel inactivation; in addition it may directly block voltage sensitive Na+ channels.
  5. S/E: Sleepiness, dizziness, diplopia, ataxia, Rash. Phenytoin: Prolongation of sodium channel inactivation.
  6. Gabapentin: Lipophilic GABA derivative which crosses to the brain and enhances GABA release, but doesnot act as agonist at GABA receptor.
  7. It is now the first line drug for pain due to diabetic neuropathy and post herpetic neuralgia.
  8. Topiramate: Weak carbonic anhydrase inhibitor; has broad-spectrum anticonvulsant activity.
  9. Also have other mechanisms of action like­ prolongation of Na+ channel inactivation, GABA potentiation by a post-synaptic effect and antagonism of certain glutamate receptors.
  10. S/E - Sedation, ataxia, Weight loss (weight gain by valproate), renal stones.

Tiagabine - Inhibits GABA transporter

CNS Part-1 Flashcard List

58 flashcards
1)
2)
3)
4)
5)
6)
7)
8)
9)
10)
11)
12)
13)
14)
15)
16)
17)
18)
19)
20)
21)
22)
23)
24)
25)
26)
27)
28)
29)
30)
31)
32)
33)
34)
35)
36)
37)
38)
39)
40)
41)
42)
43)
44)
45)
46)
47)
48)
49)
50)
51)
52)
53)
54)
55)
56)
57)
58)