This Article  • Full text  • PDF  • Reply to article  • Send to a friend  • Save in My Folder  • Save to citation manager  • Permissions  Citing Articles  • Contact me when this article is cited  Related Content  • Similar articles in this journal  Topic Collections  • Audiology  • Hearing Loss/ Deafness  • Middle/ External Ear Disorders  • Drug Therapy  • Adverse Effects  • Alert me on articles by topic  Social Bookmarking   What's this?

Leslie E. Lemke, PhD, DABT; David H. McGee, PhD, DABT; Diane M. Prieskorn, LVT, LATG; G. Michael Wall, PhD; David F. Dolan, PhD; Richard A. Altschuler, PhD; Josef M. Miller, PhD

Arch Otolaryngol Head Neck Surg. 2009;135(6):575-580.

Objective  To investigate the ototoxic potential of ciprofloxacin hydrochloride, 0.3%, plus dexamethasone, 0.1%, after administration to the guinea pig middle ear.

Design  Fifty guinea pigs were randomly assigned to 4 test groups of 10 animals each and 2 control groups of 5 animals each. The 4 test groups were treated twice daily for 4 weeks with 10 µL of (1) ciprofloxacin hydrochloride, 0.3%, plus dexamethasone, 0.1%; (2) ciprofloxacin hydrochloride, 1.0%, plus dexamethasone, 0.3%; (3) ciprofloxacin hydrochloride, 0.3%, or (4) vehicle. The positive and negative control groups were treated with neomycin sulfate, 10%, or isotonic sodium chloride solution, respectively.

Setting  Academic research laboratory.

Interventions  Study animals were implanted with a drug delivery cannula to the middle ear, terminating in the round window niche for direct delivery to the round window membrane.

Main Outcome Measures  Auditory brainstem responses were collected at baseline and following 2 and 4 weeks of dosing. At the termination of the study, inner ear tissues were evaluated microscopically.

Results  No biologically relevant hearing losses were observed after either 2 or 4 weeks of treatment with vehicle, ciprofloxacin alone, or combinations of ciprofloxacin plus dexamethasone. Examination of the organ of Corti revealed normal hair cell counts in all animals that received isotonic sodium chloride solution, vehicle, ciprofloxacin, or combinations of ciprofloxacin and dexamethasone. Conversely, the neomycin sulfate positive control group demonstrated a significant elevation in hearing threshold and profound hair cell loss (P <.001, P  = .02, and P <.001 at 2, 8, and 16 kHz, respectively).

Conclusion  The results of this preclinical study support the safety of ciprofloxacin hydrochloride, 0.3%, plus dexamethasone, 0.1%, for clinical use in the open middle ear cavity.

Author Affiliations: Alcon Research Ltd, Fort Worth, Texas (Drs Lemke, McGee, and Wall); and Kresge Hearing Research Institute, University of Michigan, Ann Arbor, (Ms Prieskorn and Drs Dolan, Altschuler, and Miller).

CiteULike    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter     What's this?