Assessment of the ototoxicity of almond oil in a chinchilla animal model.

Almond oil is frequently prescribed as a ceruminolytic, to soften ear wax or relieve ventilation tube occlusion. Ceruminolytics could lead to ototoxicity in the presence of a tympanic perforation. Reports on the safety of almond oil as a ceruminolytic is limited. The present study aimed to assess the effect of ototopic almond oil on hearing. Prospective, randomized, controlled trial in a chinchilla animal model. Bilateral myringotomies were performed in 19 female chinchilla. One randomly selected ear received almond oil, whereas the other ear received saline applied transtympanically. Auditory Brainstem Response (ABR) testing was performed prior to application and at 14 and 30 days following application. Postmortem Scanning Electron Microscopy (SEM) images were obtained to assess cochlear hair cell status. At 30 days following application, there was no significant change in ABR thresholds at 16, 20, or 25 kHz. No cochlear hair cell loss was observed with SEM. In the chinchilla, when a tympanic perforation is present, almond oil does not seem to cause ototoxicity. Further studies are needed to better assess the effect of almond oil on hearing in humans.