Causes of Rapid Hearing Loss and Sudden Deafness

It may be unsettling to learn that it's possible for you to have normal hearing your entire life and, one day, wake up deaf. You can also have mild hearing impairment and lose the rest of your hearing within a few days. This, known as sudden deafness or sudden sensorineural hearing loss (SSHL), can happen in one or both ears. Luckily, many cases are temporary or treatable.

Sudden deafness is rare, impacting one person per 5,000 annually, most often adults in their 40s and 50s. The actual number could be much higher because many people recover quickly and never see a healthcare provider.

But don't let that dissuade you from seeking an evaluation. The underlying cause may be significant, related or unrelated to your ears, and call for immediate (and, in some cases, ongoing) treatment.

Symptoms

Sudden sensorineural hearing loss (SSHL) is the rapid loss of hearing either at once or over several days. Some people don't go to a healthcare provider right away because they attribute their hearing loss to earwax in the ear canal, a sinus infection, or allergies. Unfortunately, delaying a visit to a medical professional may decrease the effectiveness of treatment or result in a serious condition going undiagnosed.

Nine out of ten 10 people with sudden deafness lose hearing in only one ear. People may experience it differently. SSHL may:

• Occur overnight (people discover it when they wake up in the morning)
• First become noticeable after doing an audio-centric activity, such as answering a phone or using earbuds
• Cause a loud popping sound just before going deaf
• Cause ringing in their ears (tinnitus), dizziness, imbalance, and vertigo

Causes

Many cases of SSHL are idiopathic, or spontaneous with no known cause.

When a cause can be identified, the most common ones are:

• Infectious diseases like viruses (e.g., Lyme disease, bacterial meningitis)
• Trauma, particularly a head injury
• Autoimmune diseases, such as Cogan’s syndrome
• Ototoxic drugs (i.e., those that cause chemical damage to the inner ear that results in permanent or temporary hearing loss): Examples include platinum-based chemotherapy, aminoglycoside antibiotics, and even large doses of aspirin).
• Blood circulation problems
• Barotrauma, or a pressure imbalance between the inner and outer ear
• A tumor on the nerve that connects the ear to the brain
• Neurologic diseases and disorders, such as migraine and multiple sclerosis
• Disorders of the inner ear, such as Ménière’s disease

This is a limited list; your SSHL may be due to several causes of varying concern.

Diagnosis

A general practitioner may refer you to an audiologist, a specialist who assesses hearing and balance problems, as well as an otolaryngologist (ear, nose, and throat doctor), who treats SSHL.

You'll most likely undergo a hearing test called pure tone audiometry, which can show the range of hearing that’s been lost. A hearing test targets two aspects of sound: Decibels, or the volume of sound, and frequencies, a measure of pitch from high to low. Sudden deafness is indicated if a hearing test shows a loss of at least 30 decibels in three connected frequencies.

If you are diagnosed with sudden deafness, other tests like blood work, magnetic resonance imaging (MRI), and balance tests can help determine an underlying cause.

Treatment

Given the large range of potential causes, treatment will largely depend on what your healthcare provider finds from testing and examinations.

In cases of physical injury or barotrauma, the ear may heal on its own. Corticosteroids are the most common treatment for sudden deafness, as they reduce inflammation, decrease swelling, and help the body fight illness. 

Additional treatments may be needed. For example, if your sudden deafness is caused by an infection, you may be prescribed antibiotics. If you have an autoimmune condition that causes your immune system to attack the inner ear, you may need to take drugs to suppress your immune system.

For cases where hearing is not fully restored, hearing aids may be an option. The key is seeing a medical professional as soon as possible to find the best treatment.