Vigabatrin exerts its antiepileptic action by irreversibly inhibiting GABA transaminase, thereby raising brain GABA levels. Its use is severely restricted because of which adverse effect?

• A Progressive myoclonus
• B Dose-dependent peripheral neuropathy
• C Aplastic anemia
• D Irreversible concentric visual field constriction ✓

Explanation

Vigabatrin produces bilateral concentric narrowing of the visual field that is often permanent and may not be noticed by the patient, so regular ophthalmologic assessment is mandatory during therapy. It remains useful for infantile spasms and refractory focal seizures where benefit outweighs this risk. Aplastic anemia is the signature toxicity of felbamate, not vigabatrin, and peripheral neuropathy is not its characteristic limitation.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.