vitamins and antioxidants
vasodilators
betahistine (Betaserc), an anti-vertigo drug
hyperbaric oxygen
rheologic agents that reduce blood viscosity (such as hydroxyethyl starch, dextran and pentoxifylline)
anti-inflammatory agents, primarily oral corticosteroids such as prednisone, methylprednisone
Intratympanic administration – Gel formulations are under investigation to provide more consistent drug delivery to the inner ear. Local drug delivery can be accomplished through intratympanic administration, a minimally invasive procedure where the ear drum is anesthetized and a drug is administered into the middle ear. From the middle ear, a drug can diffuse across the round window membrane into the inner ear. Intratympanic administration of steroids may be effective for sudden sensorineural hearing loss for some patients, but high quality clinical data has not been generated. Intratympanic administration of an anti-apoptotic peptide (JNK inhibitor) is currently being evaluated in late-stage clinical development. Epidemiology
General hearing loss affects close to 10% of the global population. In the United States alone, it is expected that 13.5 million Americans have sensorineural hearing loss. Of those with sensorineural hearing loss, approximately 50% are congenitally related. The other 50% are due to maternal or fetal infections, post-natal infections, viral infections due to rubella or cytomegalovirus, ototoxic drugs, exposure to loud sounds, severe head trauma, and premature births Of the genetically related sensorineural hearing loss cases, 75% are autosomal recessive, 15-20% autosomal dominant, and 1-3% sex-linked.
Sensorineural hearing loss (SNHL) is a type of hearing loss in which the root cause lies in the inner ear or sensory organ (cochlea and associated structures) or the vestibulocochlear nerve (cranial nerve VIII). SNHL accounts for about 90% of reported hearing loss. SNHL is usually permanent and can be mild, moderate, severe, profound, or total. Various other descriptors can be used depending on the shape of the audiogram, such as high frequency, low frequency, U-shaped, notched, peaked, or flat. Sensory hearing loss often occurs as a consequence of damaged or deficient cochlear hair cells. Hair cells may be abnormal at birth or damaged during the lifetime of an individual. There are both external causes of damage, including infection, and ototoxic drugs, as well as intrinsic causes, including genetic mutations. A common cause or exacerbating factor in SNHL is prolonged exposure to environmental noise, or noise-induced hearing loss. Exposure to a single very loud noise such as a gun shot or bomb blast can cause noise-induced hearing loss. Using headphones at high volume over time, or being in loud environments regularly, such as a loud workplace, sporting events, concerts, and using noisy machines can also be a risk for noise-induced hearing loss. Neural, or "retrocochlear", hearing loss occurs because of damage to the cochlear nerve (CVIII). This damage may affect the initiation of the nerve impulse in the cochlear nerve or the transmission of the nerve impulse along the nerve into the brainstem.