What medications are ototoxic in patients with a compromised tympanic membrane?

Medications to Avoid with Compromised Tympanic Membrane

When the tympanic membrane is compromised (perforated or has tympanostomy tubes), clinicians should prescribe only non-ototoxic topical preparations to avoid potential damage to middle ear structures and hearing loss. 1, 2

Ototoxic Medications to Avoid

• Aminoglycosides are the primary class of ototoxic medications that should be avoided in patients with perforated tympanic membranes:

  • Gentamicin - associated with severe vestibulotoxicity when used topically in the presence of tympanic membrane perforation 3, 4
  • Neomycin - can cause severe inner ear damage even at low concentrations 5
  • Tobramycin - while possibly less ototoxic than gentamicin in the first week of use, still poses significant risk with prolonged use 6

• Combination products containing aminoglycosides should also be avoided:

  • Triamcinolone/neomycin/gramicidin/nystatin (Tri-Adcortyl cream) has been associated with total hearing loss when used in patients with perforated tympanic membranes 7
  • Gentamicin/steroid combinations (e.g., Garasone) have caused documented cases of vestibulotoxicity 4

Mechanism of Ototoxicity

• Ototoxic medications can enter the middle ear through a perforation and damage inner ear structures 2
• While hearing loss may not occur after a single short course of therapy, severe hearing loss has been observed after prolonged or repetitive administration of topical ototoxic drops 1
• Vestibular toxicity (dizziness, vertigo) appears to be more common than cochlear toxicity (hearing loss) with topical aminoglycoside exposure 3, 4

Safe Alternatives

• Non-ototoxic topical preparations should be used when treating patients with known or suspected tympanic membrane perforations 1, 2
• For patients with tympanostomy tubes, quinolone ear drops have not shown ototoxicity and are recommended over systemic antibiotics 1
• For ear canal infections with significant edema in patients with perforations, a wick made of compressed cellulose (not cotton) may be used to facilitate drug delivery of non-ototoxic preparations 2

Risk Factors for Increased Ototoxicity

• Prolonged use (>7 days) significantly increases risk of ototoxicity 3
• Bilateral perforations pose greater risk for debilitating vestibular symptoms 4
• Certain mitochondrial DNA variants may increase susceptibility to aminoglycoside ototoxicity, though ototoxicity can occur even in patients without these genetic predispositions 8, 5

Clinical Recommendations

• Always examine the tympanic membrane carefully before prescribing topical ear medications 1
• If the tympanic membrane cannot be visualized due to swelling or discomfort, consider tympanometry to help establish its integrity 1
• Assume a patent tympanostomy tube is present in any child who had tubes placed less than a year ago 1
• Keep the ear dry to prevent infection when a perforation is present 2
• Avoid ear canal irrigation when tympanic membrane perforation is present or suspected 2
• Do not use cotton-tipped applicators in the ear canal as they may cause further trauma 2

Monitoring

• Monitor for signs of ototoxicity including dizziness, vertigo, tinnitus, and hearing loss 8
• If ototoxicity is suspected, discontinue the medication immediately 8
• Consider audiometric testing for patients at high risk or with symptoms of hearing loss 1