Possible hearing loss due to aspirin ?

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From : http://en.wikipedia.org/wiki/Salicylic_acid

Salicylic acid has an ototoxic effect,[citation needed] and can induce transient

hearing loss

in zinc-deficient individuals. This finding is based on clinical studies with

rats. An

injection of salicylic acid induced hearing loss in zinc-deficient rats, while a

simultaneous

injection of zinc reversed the hearing loss. An injection of magnesium in the

zinc-deficient

rats did not reverse the salicylic acid-induced hearing loss.[citation needed]

From : http://en.wikipedia.org/wiki/Aspirin

Large doses of salicylate or salicylic acid, a compound in aspirin, produces

hearing loss in

humans.[42] When this chemical is released into the body it blocks the prestin

(the motor

protein in the outer hairs of the ear). 112 rats were conditioned to respond to

a stimulus

of a 10 kHz tone. Over a four day period they were injected daily with either

saline (a

solution used as a plasma substitute) or 300mg/kg of salicylate. These

injections were

given two hours before the test period. By the fourth day the results indicated

that the rats

receiving saline did not show any results of hearing loss, in fact they improved

their

response to the sound. On day one they had a hearing score of 87%, day two 90%

and on

day four they received a hearing score of 88% (2003). However, the rats in the

salicylate

group decreased in their hearing ability over the four day period. On day one

they were at

a 91% positive response rate, on day two 83% and day four they had a response

rate of

79%. The degree of sensitivity and frequency selectivity of the cochlea (spiral

structure in

inner ear containing tiny hairs whose movement is recognized by the brain as

sound) is

due to the active mechanism generated by the outer layer hair cells. They induce

a

nonlinearity of the cochlea that can be easily recorded by a sensitive

microphone placed in

the ear canal. Cumulative injections of salicylate decreased the amplitude in

the ear canal.

This leads up to the disappearance of the noise on the third and fourth days of

the

experiment (2003).