A child treated for infantile spasms with vigabatrin achieves good seizure control. Before continuing therapy, which specific adverse effect mandates regular ophthalmologic assessment?

• A Irreversible concentric visual field constriction ✓
• B Cataract formation
• C Optic neuritis with papilloedema
• D Retinal detachment

Explanation

Vigabatrin irreversibly inhibits GABA transaminase, raising brain GABA concentrations, and is effective against infantile spasms and refractory focal seizures. Its limiting toxicity is progressive, often irreversible bilateral concentric constriction of the visual field, related to retinal GABA accumulation, requiring baseline and periodic visual field testing. Optic neuritis is associated with ethambutol, not vigabatrin, which distinguishes the distractor.

Reference: Goodman and Gilman's The Pharmacological Basis of Therapeutics, 14th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.