An internist orders rapid intravenous furosemide 80 mg undiluted over two minutes in an elderly patient simultaneously starting gentamicin for sepsis. Two days later the patient complains of hearing loss. The most likely explanation is:

• A Autoimmune inner ear disease triggered by the sulfonamide group
• B Hyponatremia causing cerebral edema with auditory symptoms
• C Gentamicin-induced cochlear damage potentiated by furosemide ✓
• D Furosemide crystallization in the endolymph

Explanation

Loop diuretics are ototoxic, and furosemide synergistically potentiates aminoglycoside ototoxicity, especially when given rapidly intravenously or concurrently. Both agents injure the stria vascularis and outer hair cells of the cochlea. Rapid IV push of furosemide alone causes transient hearing loss even without an aminoglycoside, but permanent loss here is best explained by the combination. Hyponatremia does not produce isolated sensorineural deafness.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.