Vol. 94 No. 12 December　2001

Topical Drug Therapy for Inner Ear Disorders

   There is growing otologic interest in treating inner ear disorders with topical drug therapy, for example using steroids or gentamicin. According to recent studies, intratympanic administration resulted in higher perilymph steroid levels than intravenous administration. In addition, glucocorticoid receptor was noted in the cochlea after sound exposure. These results suggest that topical administration of steroid may be useful for acute inner ear disorders.
   Topical treatment of gentamicin is effective for Meniere’s disease. Low dose gentamicin therapy dose not usually caues hearing loss and can also control vertigo. This therapy is one of the most useful treatments for Meniere’s disease.
   Recently, various drug delivery systems for the inner ear were devised, and these systems have been used clinically in the USA. However, as yet there are a limited number of drugs available for the treatment of inner ear diseases. Study about the plasticity of the inner ear has been advanced, and many kinds of drugs may be useful for the recovery of the inner ear function. We made an animal model of the drug delivery system using guinea pigs to investigate the effect of these drugs on the functional recovery of both vestibular and cochlear functions. As a result, we found that steroids, ATP, and aFGF may be effective for the recovery of the inner ear function.

Key words : topical drug therapy, inner ear, steroid, gentamicin, drug delivery system