Sudden Hearing Loss: Causes, Symptoms and Why Treatment Can't Wait
Sudden sensorineural hearing loss, sometimes called sudden deafness, is a fast drop in hearing, usually in one ear, over hours to a few days. It is often mistaken for a blocked ear. Getting it checked quickly makes a real difference to recovery.
What it feels like
Many people notice it on waking, or when they pick up the phone with the affected ear. Common signs:
- hearing in one ear suddenly sounds muffled, quiet or distorted;
- a feeling of fullness or pressure in the ear;
- new ringing or buzzing (tinnitus) in that ear;
- dizziness or a spinning sensation in some cases.
Doctors define it as a loss of at least 30 decibels across three neighboring frequencies within 72 hours. In everyday terms, normal speech may suddenly sound like a whisper on one side.
How common it is and what causes it
The National Institute on Deafness and Other Communication Disorders estimates it affects one to six people in every 5,000 each year, most often adults in their late 40s and 50s, and the true number may be higher because many cases go undiagnosed.
Only about 10% of people end up with an identified cause. Known causes include viral infections, problems with blood flow to the inner ear, autoimmune disease, head injury, some medications that are toxic to the ear, inner-ear disorders such as Meniere's disease and, rarely, a benign growth on the hearing nerve. In most cases the cause stays unknown.
Source: NIDCD, Sudden Deafness
Why it's urgent
About half of people recover some or all of their hearing on their own, usually within a week or two. But nobody can predict who will, and delaying treatment lowers its chance of working. The 2019 clinical practice guideline on sudden hearing loss from the American Academy of Otolaryngology advises prompt evaluation to separate it from a simple blockage, a hearing test, and offering treatment within two weeks of onset.
A quick check you can do: hum with your mouth closed. If the hum sounds louder in the bad ear, a blockage such as wax or fluid is more likely. If it sounds louder in the good ear, the inner ear or nerve may be involved, and you should be seen the same day if you can.
How it's diagnosed
A doctor will look in the ear to rule out wax or fluid, then order pure-tone audiometry, a standard hearing test, to measure how much hearing was lost at each pitch. If the loss is sensorineural, you may also have an MRI to rule out rarer causes, plus blood tests or balance testing. The MedlinePlus page on audiometry describes the test.
Treatment
The most common treatment is corticosteroids, which reduce inflammation and swelling. They can be taken as pills or injected through the eardrum into the middle ear; an NIDCD-funded trial in 2011 found the injections worked as well as pills, which helps people who can't take oral steroids. The guideline also lists hyperbaric oxygen as an option in some cases. If a specific cause is found, such as an infection, it is treated directly.
Follow-up hearing tests track recovery. If hearing doesn't come back fully, hearing aids or, for severe one-sided loss, devices that route sound to the good ear can help.
What not to do
- Don't assume it's wax and wait a few weeks.
- Don't put drops, oils or candles in the ear before it has been examined.
- Don't rely on supplements; nothing sold over the counter treats sudden hearing loss.
After recovery
Protect the hearing you have from noise, keep blood pressure and blood sugar in range, and get regular hearing checks. Our guide to natural ways to improve your hearing covers the everyday habits, and the Audifort review explains what a typical hearing supplement contains, for those interested in daily ear support once the urgent part is over.
Recovery and outlook
Recovery depends on how severe the loss was, how old you are, whether dizziness came with it and how soon treatment started. Milder losses and losses in the middle pitches tend to recover better than profound ones. Most improvement happens in the first few weeks, though some people keep improving for a few months. A follow-up hearing test, usually within six months, shows where you have ended up. If some loss remains, an audiologist can advise on hearing aids or other devices, and tinnitus that lingers often fades or becomes less noticeable over time.
Questions readers ask
Can sudden hearing loss come back?
It usually affects one episode in one ear, but a small share of people have another episode later. Any new sudden change should be checked again.
How long do I have to get treatment?
Guidelines recommend offering steroid treatment within two weeks of onset, and earlier is better. Try to be seen within a few days.
Is sudden hearing loss a sign of a stroke?
Rarely, especially when it comes with dizziness, weakness, numbness or trouble speaking. Those symptoms together need emergency care immediately.