A 50-year-old woman receiving injectable therapy for drug-resistant tuberculosis develops gait instability, inability to walk in tandem, and nystagmus, with normal pure tone audiometry. Which drug and which structure are implicated?

• A Streptomycin, vestibular apparatus ✓
• B Capreomycin, renal tubules
• C Amikacin, cochlear hair cells
• D Levofloxacin, Achilles tendon

Explanation

Streptomycin characteristically injures the vestibular apparatus rather than the cochlea, producing vertigo, nystagmus, ataxia, and loss of balance, while audiometry remains initially normal. Amikacin and kanamycin preferentially cause cochlear (hearing) loss, so their classic presentation is deafness or tinnitus rather than vestibular dysfunction. This vestibular versus cochlear split between aminoglycosides is a standard examination distinction.

Reference: Katzung Basic and Clinical Pharmacology, 16th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.