In summary, the acute effects of such drugs are primarily based on calcium antagonism and the block of ion channels. Chronic cochlear vestibular toxicity requires metabolism. The expression of tissue-specific toxicity is a balance between synthesis of a toxic metabolite and its detoxification. Only through a detailed knowledge of the molecular basis of toxicity can rational approaches be pursued in the development of new aminoglycosides as well as other drugs with less potential for serious cochlear vestibular toxicity.

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                                                      A                           B                          C                         D

Figure 14-2: Progressive hearing loss in a patient receiving Cisplatin. A, Baseline. B, one month later. C, one month later. D, one month later. Showing progressive hearing loss at the high frequencies.

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Figure 14-3: Audiogram of a patient who suffered the sudden onset of unilateral hearing loss while receiving large dose non-steroidal therapy for tendonitis.

 

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