Question

Anticonvulsant drug used as a selective molecular target

• A. Vigabatrin
• B. Gabapentin
• C. Lamotrigine
• D. Tiagabine

Hint:

Drugs targeting voltage-gated ion channels are commonly used in epilepsy. Lamotrigine is especially important due to its dual action in seizure control and bipolar disorder.

Answer 1

The Correct Option is C

Lamotrigine is an anticonvulsant and mood-stabilizing drug primarily used in the treatment of epilepsy and bipolar disorder. Its mechanism of action involves selective molecular targeting of voltage-gated sodium channels (VGSCs), thereby stabilizing neuronal membranes and inhibiting the release of excitatory neurotransmitters like glutamate and aspartate. This selective inhibition reduces the high-frequency neuronal firing associated with seizures, making lamotrigine effective in treating partial seizures, generalized seizures, and Lennox-Gastaut syndrome. - Vigabatrin inhibits GABA transaminase, increasing GABA levels—broad-acting, not highly selective.
- Gabapentin binds to the α₂δ subunit of voltage-gated calcium channels, but it’s not a classic selective target inhibitor.
- Tiagabine inhibits GABA reuptake via GAT-1, increasing GABA in the synaptic cleft—not a selective molecular blocker.
Thus, among the listed drugs, lamotrigine exhibits selective molecular targeting by acting on sodium channels, making it a key GPAT-relevant example of such a mechanism.