Garlic-Supplemented Diet Attenuates Gentamicin-Induced Ototoxicity: An Experimental Study

Objectives: Gentamicin sulfate is a potent aminoglycoside antibiotic associated with serious side effects, including ototoxicity. Garlic, with its intrinsic antioxidant activity, may prove beneficial in prevention of ototoxicity. In this study, we investigated the effect of a 4% garlic supplemented diet on the ototoxicity induced by gentamicin in rats by using brain stern evoked response audiometry. Methods: Eighteen male Wistar rats with an intact Preyer's reflex and an initial weight of 220 to 260 g were randomly assigned to a group with gentamicin injection and garlic supplementation, a group with gentamicin injection without garlic supplementation, or a control group (6 rats each group). Gentamicin was given by intraperitoneal injection at 120 mg/kg body weight once daily for 16 days. The garlic-supplemented diet was prepared by adding pulverized whole garlic cloves to standard chow in a 4% proportion. After 21 days, hearing thresholds were evaluated by use of brain stem evoked response audiometry at 10 kHz. Results: The mean (+/- SD) amplitudes of the auditory thresholds (sensation level) measured by use of brain stem evoked response audiometry for the group with garlic supplementation, the group without garlic, and the control group were 43.3 +/- 8.16, 78.0 +/- 4.47, and 16.7 +/- 5.16 dB sensation level, respectively. The differences were statistically significant (p < 0.05). Conclusions: A garlic-supplemented diet seems to attenuate aminoglycoside-induced hearing loss.