Acoustic trauma and other insults to the inner ear may trigger increased levels of extra-cellular glutamate, which in turn cause excessive activation of cochlear NMDA receptors. This process results in damage or killing of sensory cells and is thought to be responsible for abnormal spontaneous "firing" of auditory nerves, which may be perceived as tinnitus. Under normal circumstances, the NMDA receptors are thought to play no role in fast excitatory neurotransmission, respectively normal hearing. Keyzilen ® is blocking cochlear NMDA receptors to suppress the aberrant excitation of the auditory nerve that is perceived as tinnitus.
The most common treatment for sudden deafness, especially in cases where the cause is unknown, is corticosteroids. Steroids are used to treat many different disorders and usually work by reducing inflammation, decreasing swelling, and helping the body fight illness. Steroids are usually prescribed in pill form. In recent years, direct injection of steroids behind the eardrum into the middle ear (from here the steroids travel into the inner ear), called intratympanic corticosteroid therapy, has grown in popularity. In 2011, a clinical trial supported by the NIDCD showed that intratympanic steroids were no less effective than oral steroids , but were less comfortable overall for patients. They remain an option for people who can’t take oral steroids.
Although the cause is unknown, Menieres disease probably results from an abnormality in the volume of fluid in the inner ear. Too much fluid may accumulate either due to excess production or inadequate absorption. In some individuals, especially those with involvement of both ears, allergies or autoimmune disorders may play a role in producing Ménières disease. In some cases, other conditions may cause symptoms similar to those of Ménières disease.
People with Ménières disease have a sick inner ear and are more sensitive to factors, such as fatigue and stress, that may influence the frequency of attacks.