Sudden hearing loss in one ear is a medical emergency. If you lose hearing in one ear suddenly – over hours or days, sometimes with ringing or a feeling of fullness – you should be seen by a doctor or ENT specialist within 72 hours. Delayed treatment can mean permanent hearing loss that could otherwise have been recovered.

This guide explains what sudden sensorineural hearing loss (SSNHL) is, why the 72-hour window matters, what causes it, and exactly what to do if it happens to you or someone close to you.

What counts as sudden hearing loss?

Sudden sensorineural hearing loss is a rapid loss of hearing – typically developing over a few hours, or overnight, in one ear. People commonly describe it as:

• Waking up with one ear blocked or “switched off”
• A pop followed by immediate muffled hearing
• New ringing (tinnitus) in one ear with reduced hearing
• Fullness or pressure in the ear, sometimes with dizziness

It affects roughly 5 to 20 people per 100,000 each year, and while it can happen at any age, it’s most common between 40 and 60.

Why the 72-hour window matters

Most cases of sudden sensorineural hearing loss are treated with corticosteroids, which reduce inflammation of the inner ear and hearing nerve. Clinical evidence shows steroid treatment is most effective when started as early as possible, ideally within 24-72 hours of onset. After two weeks, the chance of meaningful recovery drops substantially.

That’s what makes this different from gradual age-related hearing loss, where waiting a few weeks for an appointment changes little. With sudden loss, time is hearing.

What causes sudden hearing loss in one ear?

Despite how alarming it feels, only about 10-15% of cases have an identifiable cause. Known causes and contributors include:

• Viral infections (including herpes simplex reactivation in the inner ear)
• Circulation problems reducing blood flow to the cochlea
• Autoimmune inner ear disease
• Head injury or barotrauma (diving, flying with congestion)
• Certain medications that are toxic to the ear
• Rarely, tumours such as acoustic neuroma

In most cases no cause is found, which is why the condition is also called idiopathic sudden sensorineural hearing loss.

Sudden hearing loss or just ear wax? How to tell

Not every blocked ear is an emergency. A wax blockage usually builds gradually, often after cotton bud use or hearing aid wear, and hearing often improves slightly when you wiggle your jaw. Sudden sensorineural loss, on the other hand:

• Happens within hours, not weeks
• Often comes with high-pitched ringing in that ear
• Doesn’t improve when you clear the outer ear
• Can come with dizziness or balance changes

You can’t reliably tell the difference yourself – a quick ear examination and hearing test can. The safest rule: any sudden hearing change gets checked within 72 hours. If wax is the cause, removal takes minutes; if it’s sensorineural loss, you’ve caught it inside the treatment window.

What to do right now (step by step)

1. Don’t wait to see if it settles. Sudden hearing loss rarely resolves on its own within the treatment window.
2. See your GP or an ENT urgently today. Ask specifically for assessment of sudden sensorineural hearing loss.
3. Get a hearing test immediately. An audiologist can perform a diagnostic assessment the same day to confirm whether the loss is sensorineural (emergency) or conductive (often wax/fluid, less urgent).
4. Don’t insert anything into the ear – no cotton buds, drops, or irrigation before examination.
5. If dizziness is severe, or you have new weakness, facial droop, or double vision, go to an emergency department – these need stroke assessment.

How is sudden hearing loss treated?

Standard treatment is corticosteroids – either tablets over 1-2 weeks or steroid injections through the eardrum (intratympanic injection) for persistent cases. Your ENT may also investigate underlying causes with MRI. If some hearing remains reduced after treatment, hearing rehabilitation options exist, including hearing aids and single-sided solutions like CROS/BiCROS fittings.

At Clear Hearing Solutions, we reserve same-day urgent appointments for sudden hearing changes. If you’re in Hamilton, Thornlands or the wider Brisbane/Redlands area and notice sudden loss in one ear, call us immediately on 0435 883 554 – outside business hours, contact your GP or nearest emergency department.

Can sudden hearing loss recover?

Yes – roughly half to two-thirds of people recover some or all hearing, and early treatment is the single biggest factor in recovery. People treated within 72 hours have significantly better outcomes than those treated after two weeks. Recovery, when it happens, typically occurs over days to weeks.

Sudden hearing loss FAQ

Is sudden hearing loss in one ear an emergency?

Yes. Sudden sensorineural hearing loss should be assessed within 72 hours – ideally within 24. Steroid treatment works best the earlier it starts, and delays can result in permanent hearing loss.

What is the most common cause of sudden hearing loss?

Most cases are idiopathic (no identified cause). Identified causes include viral infection, reduced cochlear blood flow, autoimmune disease, head injury, and some medications. An ENT assessment helps rule out treatable or dangerous causes.

Can ear wax cause sudden hearing loss?

Wax usually causes gradual blockage, but a complete occlusion can feel sudden. The only way to distinguish wax from sensorineural loss is examination plus a hearing test – both are quick, so don’t gamble on the cause.

Should I go to the hospital for sudden hearing loss?

If you can’t reach your GP or an urgent audiology/ENT appointment within 72 hours, an emergency department is appropriate – especially with dizziness, severe imbalance, or neurological symptoms.