Examination of ototoxicity induced by imatinib, being a tyrosine kinase inhibitor: An experimental study

Objectives: Two rats were excluded from the study. Because otitis media developing one rat in Group C (7^thdayof the experiment) and bleeding-related death one rat in Group I-50 (14^thday of the experiment). While the side effects of imatinib are investigated in the literature, it is remarkable that the case reports suggesting an ototoxic side effect also take place among the publications. The aim of this study was to investigate whether or not imatinib has any ototoxic effect on rats via auditory brainstem response (ABR) responses. Materials and Methods: Rats were divided into three groups as Group C (0.25 mL/kg/day), Group I-30 (30 mg/kg/day), and Group I-50 (50 mg/kg/day). In the ABR record, hearing threshold, latency, amplitude, and interpeak latency values on test days were recorded and assessed. Results: In the assessment made in terms of mean V Wave latency within the group, a difference was determined at all stimulus intensities at 8 kHz in Group I-50 (P < 0.05). In the within-group assessment performed in terms of mean Wave III latency, there were differences in Groups I-30 and I-50 (P < 0.05). In the within-group assessment performed in terms of I-III interpeak latency mean values, there was a difference at 4 kHz and 70 dB in Group I-30 (P < 0.05). In the within-group assessment in terms of mean III-V interpeak latency values, the difference between the groups was significant on the 7^thday at 6 kHz and 50 dB (P = 0.044) and on the 14^thday at 8 kHz and 70 dB (P = 0.036). In the within-group assessment in terms of Wave I amplitude mean values, the change in the amplitude values at 4 kHz (P = 0.003) and 6 kHz (P = 0.018) in Group I-50 was significant. Conclusion: It was observed that imatinib application caused elongation in latency and interpeak latency values and changes in amplitude values. These differences were not enough to state that imatinib is having an ototoxic side effect.