Sudden hearing loss can happen unexpectedly and may affect one or both ears. A person may notice that sounds suddenly seem quieter, speech becomes difficult to understand, or one ear feels blocked.
Although some hearing changes may be caused by common problems such as earwax or an ear infection, sudden hearing loss can sometimes be linked to an inner-ear problem called sudden sensorineural hearing loss (SSNHL).
Because some forms of sudden hearing loss need prompt medical assessment and treatment, it should not simply be assumed to be earwax, congestion, or a temporary blockage. Early evaluation may improve the chance of hearing recovery.
Understanding the warning signs, possible causes, diagnosis, and treatment options can help people seek appropriate care without unnecessary delay.
What Is Sudden Hearing Loss?
Sudden hearing loss means that hearing decreases rapidly, usually over a short period. Sudden sensorineural hearing loss is a specific type that involves the inner ear or the hearing pathway.
SSNHL commonly affects one ear. It may develop all at once or become noticeable over a few days.
The condition may be noticed when:
- One ear suddenly sounds quieter
- Speech becomes difficult to understand
- Sounds seem muffled
- There is a feeling of fullness in the ear
- Ringing or buzzing develops
- Dizziness or imbalance occurs
According to the National Institute on Deafness and Other Communication Disorders, sudden sensorineural hearing loss should be treated as a medical emergency because delaying assessment and treatment can reduce the effectiveness of treatment when treatment is appropriate.
Why Should Sudden Hearing Loss Never Be Ignored?
Sudden hearing loss can have several possible causes. Some are temporary and treatable, while others may affect the inner ear or hearing nerve.
For example, hearing may suddenly seem reduced because of earwax or fluid in the middle ear. However, a similar sensation can occur with sensorineural hearing loss.
Therefore, it is not always possible to identify the cause simply by how the ear feels.
A doctor can examine the ear and arrange a hearing test when needed. This helps distinguish a blockage or middle-ear problem from an inner-ear hearing loss.
Common Signs of Sudden Hearing Loss
Sudden hearing loss may be accompanied by different symptoms.
Common signs include:
- Sudden reduction in hearing
- Hearing loss mainly in one ear
- Muffled or unclear sounds
- Difficulty understanding conversations
- Ear fullness or pressure
- Ringing or buzzing in the ear
- Dizziness or imbalance
Some people may notice the problem immediately after waking up. Others may discover it while using a telephone or listening to someone speak.
Because symptoms can vary, sudden changes in hearing should be assessed promptly.
Sudden Hearing Loss in One Ear
Sudden hearing loss often affects only one ear.
A person may notice that one side sounds quieter while the other ear appears normal. This can make the problem easy to overlook, particularly in a noisy environment.
However, sudden hearing loss in one ear still requires medical evaluation.
In some cases, doctors may recommend further investigations to look for problems affecting the hearing nerve or structures behind the inner ear. MRI or other appropriate tests may be considered depending on the clinical situation.
Ear Fullness and Hearing Loss
A blocked or full sensation in the ear does not always mean that earwax is responsible.
Sudden sensorineural hearing loss can also cause a feeling of fullness or pressure in the affected ear.
Therefore, repeatedly trying to clean the ear or waiting for the sensation to disappear may delay proper evaluation.
If ear fullness appears together with sudden hearing loss, ringing, or dizziness, medical assessment is particularly important.
Ringing in the Ear Along With Hearing Loss
Tinnitus means hearing a sound such as ringing, buzzing, humming, or whistling when there is no external source.
Tinnitus can occur for many reasons. However, when ringing develops suddenly along with a noticeable reduction in hearing, it should not be ignored.
A hearing assessment can help determine whether the symptoms are associated with sensorineural hearing loss or another ear problem.
Dizziness and Sudden Hearing Loss
Some people with sudden hearing loss may also experience dizziness or imbalance.
This happens because the inner ear is involved in both hearing and balance.
However, dizziness can have many different causes. Therefore, the combination of sudden hearing loss and dizziness should be assessed by a healthcare professional rather than treated as a simple ear blockage.
What Causes Sudden Hearing Loss?
There may be several possible causes of sudden hearing loss.
These can include:
- Inner-ear disorders
- Viral or other infections
- Head or ear trauma
- Autoimmune conditions
- Certain medicines that can affect hearing
- Blood circulation problems
- Neurological conditions
- Ménière’s disease
- Problems affecting the hearing nerve
However, in many cases of sudden sensorineural hearing loss, an exact cause cannot be identified.
Therefore, medical evaluation is important even when there is no obvious reason for the hearing change.
Can Earwax Cause Sudden Hearing Loss?
Yes, earwax can cause conductive hearing loss and make sounds seem blocked or muffled.
However, earwax is not the only possible explanation for sudden hearing changes.
This is why people should avoid assuming that a sudden loss of hearing is simply due to wax.
A healthcare professional can examine the ear and determine whether an obstruction is present. If necessary, a hearing test can then help identify the type and severity of hearing loss.
How Is Sudden Hearing Loss Diagnosed?
Doctors usually begin with a detailed medical history and examination of the ear.
The evaluation may include:
- Examination of the ear canal and eardrum
- Hearing assessment
- Pure-tone audiometry
- Additional hearing tests when required
- Imaging such as MRI in selected cases
- Other investigations depending on the suspected cause
Audiometry is particularly important because it can confirm the type and degree of hearing loss.
The AAO-HNS guideline recommends obtaining or referring for audiometry as soon as possible, and within 14 days of symptom onset, to confirm sudden sensorineural hearing loss.
Importance of a Hearing Test
A hearing test provides more information than simply asking whether a person can hear.
Pure-tone audiometry measures how well a person hears different sound frequencies and helps determine the degree and type of hearing loss.
As a result, it can help doctors distinguish sensorineural hearing loss from conductive hearing loss.
Because treatment decisions may depend on the type and timing of hearing loss, timely hearing assessment is important.
