Otoxic Effects Of Cisplatin

Ototoxicity may be defined as “damage to the structure and function of the inner ear (auditory, vestibular, or both) that results from exposure to toxins” (Campbell, 2007). Exposure to toxins is often the result of the administration of therapeutic agents or medications for the treatment of other primary diagnoses. These medications fall into several classes including: aminoglycoside antibiotics, antineoplastic drugs, other antibiotics, antimalarial drugs, loop diuretics, and salicylates. To date, there are over 200 over-the-counter and prescription medications that are known ototoxic articles. (Fausti et. al, 2007). This document will specifically focus on the ototoxicity of the antineoplastic agent cisplatin. Rosenburg and his team first …show more content…
Individuals undergoing high cumulative doses of cisplatin are more likely to experience increased hearing thresholds and tinnitus. Upon its introduction, the standard dosage of cisplatin was 50 mg/m2. More aggressive forms of treatment today may administer up to 225 mg/m2 of cisplatin resulting in significant increases in ototoxic effects (Rybak et al. 2007b). Laurell and Jungnelius reported that for 50 patients receiving very high-dose cisplatin treatment (100-120 mg/m2) 81% experienced significant elevations in air-conduction thresholds (greater than 15dB at one frequency and elevations of 10dB or more in three frequencies). After completion of seven courses of cisplatin administration, 41% of these high-dose cisplatin patients experienced significant hearing losses between 500 and 2,000 Hz –the important frequency range for human speech (Laurell & Jungnelius, 1990). Additional research regarding high dosages of cisplatin (70-85 mg/m2) revealed that 42% of these individuals experienced significant ototoxic symptoms after six courses of weekly treatment (de Jong et al. 2003). Furthermore, Vermorken et al. have reported that only 20% of patients receiving low doses of cisplatin (< 50 mg/m2) develop ototoxicity, while 75-100% receiving very high doses develop ototoxicity …show more content…
Children under the age of five and elderly adults are most susceptible to cisplatin ototoxicity (Rybak et al. 2007b) and approximately 60% of patients ages 8 months to 20 years will incur irreversible hearing loss after cisplatin treatment (Knight et al 05, 07, integrated view….). In addition to high cumulative doses and age, renal insufficiency, additional head and neck radiation therapy and pre-existing hearing loss also increase individual’s likelihood of experiencing cisplatin-induced