Ototoxicity of ototopical drops--an update

Area of Science:

• Otolaryngology
• Pharmacology
• Toxicology

Background:

• Topical otic preparations are common treatments for various ear conditions, including external otitis and otitis media.
• When the tympanic membrane is perforated, middle ear solutions can access the inner ear via the round window membrane.
• Concerns exist regarding the ototoxic potential of common otic solution components, such as aminoglycosides, corticosteroids, solvents, and preservatives.

Purpose of the Study:

• To review existing literature on the safety of otic preparations used in cases of tympanic membrane perforation.
• To evaluate the ototoxic potential of frequently used otic solution ingredients.
• To discuss clinical and medical-legal experiences related to ototoxicity from topical ear medications.

Main Methods:

• Literature review of studies investigating the safety and ototoxicity of otic solution components.
• Analysis of clinical case reports and medical-legal data concerning ototoxicity.
• Evaluation of the pharmacokinetics and toxicological profiles of key ingredients.

Main Results:

• Certain components in otic solutions, particularly aminoglycosides, pose a risk of inner ear toxicity when the round window membrane is compromised.
• Corticosteroids, solvents, and preservatives may also contribute to ototoxicity, though evidence varies.
• Clinical and legal cases highlight the importance of careful drug selection and administration.

Conclusions:

• The use of otic preparations in patients with perforated tympanic membranes requires careful consideration of potential ototoxicity.
• Further research is needed to establish safer formulations and guidelines for otic drug delivery.
• Clinicians must weigh the benefits against the risks of ototoxicity when prescribing topical ear medications.