Vigabatrin is an antiepileptic used in infantile spasms and refractory focal seizures. Its anticonvulsant mechanism is:

• A Inhibition of GABA reuptake via neuronal GAT-1 transporter
• B Blockade of the synaptic vesicle protein SV2A
• C Irreversible inhibition of GABA transaminase, increasing brain GABA concentrations ✓
• D Selective antagonism of AMPA-type glutamate receptors

Explanation

Vigabatrin irreversibly inhibits GABA-transaminase (GABA-T), the enzyme that degrades GABA, thereby raising CNS GABA levels. Tiagabine is the agent that blocks GAT-1 reuptake; levetiracetam binds SV2C; perampanel blocks AMPA receptors. Vigabatrin's major limiting toxicity, irreversible constriction of visual fields, mandates regular ophthalmologic monitoring during therapy.

Reference: Katzung Basic and Clinical Pharmacology, 15th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.