Pregnant guinea pigs were treated with gentamicin (100 mg/kg/day intraperitoneally for seven days), with or without the addition of L-carnitine (1 mg/ml in drinking water, equivalent to approximately 100 mg/kg/day). L-carnitine was started two weeks before or simultaneously with gentamicin. Supplementation with L-carnitine at either time completely prevented gentamicin-induced hearing loss in both the mothers and the offspring.

Comment: Gentamicin-induced ototoxicity results from apoptosis of auditory and vestibular sensory cells and is irreversible. An increasing number of pregnant women are being treated with gentamicin during the perinatal period, and their offspring are therefore being exposed to this drug in utero. The results of the present study suggest that treatment with L-carnitine can prevent gentamicin-induced ototoxicity. A previous study in guinea pigs found that vitamin B12 also reduced the ototoxic effect of gentamicin (Acta Otolaryngol. 2001;121:351-354).

Kalinec GM, et al. Pivotal role of Harakiri in the induction and prevention of gentamicin-induced hearing loss. Proc Natl Acad Sci. 2005;102:16019-16024.