What Is Sudden Hearing Loss?

Sudden hearing loss, or sudden deafness, is exactly what it sounds like: loss or partial loss of the ability to hear within a very short time. It may happen all at once or gradually over several hours or days. Most often, it affects just one ear (unilateral deafness), but about 2% of the time it’s bilateral (affecting both ears).

Clinically known as “sudden sensorineural (meaning inner ear) hearing loss” or SSNHL, the condition impacts about 0.1% of people in the United States each year, mostly those over 40.

Sudden sensorineural hearlng loss may be due to injury, disease, or problems with the ear’s structure, although the exact cause in a specific person is oftentimes never revealed. It requires immediate attention to identify the cause and possibly prevent long-term deafness. 

Symptoms

The sudden acute loss of the ability to hear is often accompanied by ringing. Frequently, there's a feeling of fullness in the affected ear. In other cases, there's no such warning: The person often first notices a problem when they awake from sleep.

SSNHL can result in a total loss of hearing, an inability to hear low or high frequencies or difficulty understanding what people are saying. Up to 90% of people with sudden hearing loss in one ear or both ears suffer from tinnitus or ringing in the ear. 

Because of the ear’s role in balance, sudden deafness may be accompanied by vestibular disorders—problems related to the inner ear that affect coordination or movement. These include:

• Vertigo or dizziness
• Loss of balance
• Motion sickness
• Nausea

Causes and Risk Factors

Around 90% of cases of sudden sensorineural hearing loss cases are idiopathic, which means there's no clear cause.

In addition to infection, SSNHL may be a result of autoimmune diseases, trauma, vascular disorders, neoplasm (tumors or other growths), metabolic diseases, reactions to medications, ear problems, or neurological disorders.

Hearing loss can also be a side effect of some medications, including: antibiotics such as Garamycin (gentamicin), which is used to treat several types of bacterial infections; Lasix (furosemide) a diuretic that treats water retention and swelling; chemotherapy drugs; non-steroidal anti-inflammatories; and salicylates (found in pain killers). Many chemotherapies can cause sensoneural hearing loss.

Diagnosis

If you experience a sudden loss of hearing, your healthcare provider will first do a medical history and ask about your symptoms. They will then look inside the affected ear to check for obstructions, inflammation, fluid, or wax build-up. 

Next you'll likely undergo a general hearing test in which the healthcare provider may cover your ears one at a time and ask you to repeat words that are whispered. They also may strike a tuning fork near your ear to see if you can detect the tone it emits.

If these tests show hearing loss, you likely will be referred to an audiologist (a person who specializes in hearing issues) for further tests, which may include pure-tone testing. You’ll wear headphones into which sounds at various volumes, pitches, or frequencies are played and asked to identify when and if you hear them.

These tests help determine how loud a sound needs to be before you can hear it. Sound is measured in decibels (dB). You’ll be diagnosed with SSNHL if you cannot hear a sound below 30dB.

You may need to undergo additional tests to determine a cause for your sudden sensorineural hearing loss, depending on your medical history and other symptoms. A magnetic resonance imaging (MRI) scan, for instance, might be ordered if there’s a reason to suspect tumors. Blood tests can help to confirm or rule out infections, metabolic disorders, or autoimmune disease. 

Treatment

When needed, the first line of treatment is usually corticosteroids, which reduce inflammation and swelling in the inner ear. Typically, a course of oral steroids such as prednisone or methylprednisolone is prescribed.

Studies have shown that injecting steroids directly into the middle ear is also an effective way to treat SSNHL. These intratympanic injections may be preferable if you're concerned about side effects associated with oral corticosteroids, such as if you are pregnant or have hypertension, gastritis, or sleep disruptions.

If idiopathic SSNHL doesn't improve with steroids alone, a healthcare provider may also recommend hyperbaric oxygenation (HBO) therapy. With this course of treatment, you might be placed in a hyperbaric chamber and treated with air compression, made to breathe 100% oxygen through a mask, and undergo a decompression session.

According to research, HBO may work by reducing inflammation or because they support healthy function of the cochlea and ear structures, which require a high supply of oxygen. This therapy remains somewhat controversial and may not be paid for by many health insurances.

If your hearing loss is associated with a bacterial infection, you will be prescribed antibiotics. However, bacterial infections of the inner ear or cochlea are incredibly rare.

In cases where SSNHLis related to an autoimmune disease, you may be placed on immunosuppressant drugs to manage your symptoms.

When SSNHL is related to a reaction to a medication, your healthcare provider will likely have you switch to a different drug.

Coping

If hearing doesn’t return within six to 12 months, deafness is likely to be permanent. In those instances, support devices may be beneficial. Today’s hearing aids offer a wide range of options to amplify sound or stimulate the inner ear.

Some people with severe hearing loss are candidates for cochlear implants, devices that replace the three small bones of the middle ear to enable the deaf and hard of hearing to hear sound.

Modern technology has also made it a little easier to adapt to sudden hearing loss. Captioning on movies, television, and even YouTube videos allow you to read words that you might miss. Special teletypewriting devices that provide text communication via telephone lines (TTYs) have been around for decades to help deaf and hard-of-hearing people communicate by phone. However, texting and emailing has greatly reduced the need for TTYs. Movie theaters are often equipped with portable captioning devices so you can follow the dialogue of the latest blockbuster.

Research shows that peer-support groups are often an important way to manage stress and adapt to life with hearing loss.Talk to your healthcare provider about local groups and be open about sadness or depression so you can get help and avoid having those feelings affect your quality of life.

A Word from Verywell

Support devices have limitations, and it's not unusual to feel a sense of sadness following hearing loss. Learning to navigate the world with reduced hearing, not being able to enjoy music or everyday conversation in the same way as before, and continual discomfort due to lingering tinnitus can be extremely frustrating.

It’s believed that many cases of sudden sensorineural hearing loss may actually go undiagnosed because people dismiss problems with hearing as just “getting old,” ear wax build-up, or other problems they think will go away on their own or can’t be helped.

In truth, hearing loss should be evaluated as soon as possible. Getting timely intervention can help you prevent long-term problems or, possibly, reveal a serious medical condition. Acting right away may not only improve your hearing, it may also boost your overall health.