Ototoxicity of olive oil in a chinchilla animal model.

OBJECTIVES/HYPOTHESIS Olive oil is often used by patients to soften ear wax or to relieve ear canal obstruction. It is also sold in drugstores as a cerumenolytic. To date, no study has assessed the safety of ototopical olive oil on hearing in the presence of tympanic membrane perforation. The present study aimed to assess the safety of ototopic olive oil on hearing in the presence of tympanic membrane perforation. STUDY DESIGN Prospective, randomized, controlled trial in a chinchilla animal model. MATERIALS AND METHODS Eleven chinchillas underwent bilateral myringotomy. In each animal, one ear was randomly assigned to receive olive oil (experimental ear), while the contralateral control ear received normal saline. Auditory brain response (ABR) test was performed at baseline and then 7, 14, and 30 days following the application. RESULTS At 30 days follow-up, there was no significant change in auditory brain response thresholds at 8, 16, 20, or 25 kHz. Scanning electron microscope imaging showed no damage to the hair cells. CONCLUSION Olive oil does not seem to cause hearing loss in chinchillas with perforated tympanic membranes. Future clinical studies are required.