Sudden hearing loss: What causes it?

Sudden hearing loss is hearing loss that occurs abruptly or over a period of several days. It usually affects only one ear. Sometimes, this type of hearing loss is accompanied by a ringing in the ear (tinnitus) or dizziness. Sudden hearing loss requires immediate medical attention. Although the cause can't always be determined, known causes of sudden hearing loss include:

• Viral infection of the inner ear, such as due to the mumps, measles or chickenpox
• Disruption of blood flow to the cochlea, such as due to a head injury
• Torn membrane within a part of the inner ear (cochlea)
• Noncancerous tumor (acoustic neuroma) of the acoustic nerve

An audiologist will test your hearing to determine the extent and severity of your hearing loss. Mild hearing loss may improve within a few weeks. Depending on the underlying cause, many people with sudden hearing loss may regain their former level of hearing. Others show no improvement or regain only partial hearing in the affected ear.

Treatment of sudden hearing loss is directed at the underlying cause, if possible. If the cause isn't known, treatment may include:

• Corticosteroids
• Antiviral medications