Sudden sensorineural hearing loss (SSHL): why speed matters

Sensorineural hearing loss refers to a problem in the inner ear or the nerve that carries sound to the brain, rather than in the ear canal or middle ear. The Hull University Teaching Hospitals leaflet describes the sudden form as typically affecting one ear, developing within a 3-day period, and often described by patients as complete deafness in that ear. Dizziness and tinnitus may come with it.

NICE phrases the clinical test slightly differently, defining sudden onset as hearing loss developing over three days or less. Its quality standard separates this from hearing loss explained by outer or middle ear problems, such as swimmer's ear or a cold affecting the middle ear, which are handled differently.

Many people first notice the loss on waking, or when they put a phone to the affected ear and find the sound muffled or absent. Because it is usually painless, it is easy to put down to wax or a blocked ear and wait, which is exactly the delay the guidance is trying to prevent.

NICE states that sudden-onset hearing loss in one or both ears not explained by external or middle ear causes is an emergency. Its quality standard sets two timeframes: if the loss developed suddenly within the past 30 days, referral should be immediate so that the person is seen by a specialist within 24 hours; if it began more than 30 days earlier, referral is urgent, aiming for a specialist within 2 weeks.

NICE adds a second reason for speed beyond hearing recovery: sudden-onset sensorineural loss needs immediate or urgent investigation for treatable causes such as autoimmune disease, chronic infection, a rapidly expanding vestibular schwannoma or stroke. The Hull leaflet makes the point that medical attention should be sought as soon as possible for full assessment, a hearing test and, where appropriate, steroid treatment.

In practice, this means contacting a GP or an NHS urgent service the same day, rather than waiting for a routine appointment. If hearing loss comes with facial weakness, severe vertigo, weakness elsewhere or speech trouble, treat it as a possible stroke and call 999.

The Hull leaflet explains that an urgent hearing test confirms the diagnosis, and is repeated after the initial steroid course at an outpatient review. An MRI scan may be requested to rule out other causes. The leaflet states that less than 1% of sudden sensorineural hearing loss is due to a benign tumour on the hearing nerve called a vestibular schwannoma, and an MRI looks for it.

The urgent hearing test confirms the diagnosis. NICE separates hearing loss explained by outer or middle ear causes, such as swimmer's ear or a cold affecting the middle ear, from unexplained sudden loss, which is why the ear is examined first.

According to the Hull leaflet, steroids are the main treatment, and oral steroids should be started as soon as possible for the best hearing recovery. It also notes that after discussion with a clinician, watchful waiting may be more appropriate for some people because of the side effects of steroids.

If first-line treatment does not work or improvement is minimal, an ENT consultant may offer salvage therapy, which includes intratympanic steroids: a steroid injected into the ear through the ear drum, offered up to 6 weeks after onset. The leaflet reports side effects as mostly mild and short-lived, and gives approximate frequencies for the injection:

• Mild ear discomfort in less than half of people

• Temporary dizziness lasting a couple of minutes in less than 1 in 4

• Ear infection in less than 1 in 20

• A permanent hole in the ear drum in less than 1 in 100

• Allergic reaction or further hearing loss in the injected ear in fewer than 1 in 1,000

The leaflet reports that half of people with sudden sensorineural hearing loss recover at least some hearing without treatment, but that this is difficult to predict, and that earlier steroid treatment gives better chances. People with mild to moderate loss are described as being in a steroid-effective zone, with a high chance of recovery (over 75%), whereas profound loss, associated dizziness and age above 65 are linked to a lower chance. Hearing can take 6 weeks or more to return even after treatment ends.

The emotional side deserves attention. The leaflet acknowledges that the condition can be frightening and cause anxiety, loneliness, isolation and depression, and that tinnitus can be loud at first but is expected to reduce as hearing improves. If recovery is incomplete, referral to audiology for hearing aids or other devices may be appropriate.

The NICE standard envisages assessment through an ENT service, an audiovestibular medicine service or an emergency department, with locally agreed referral pathways. Because the first days matter most, the NHS emergency or urgent route is generally the quickest, and a routine private appointment weeks away is not a substitute.

Private ENT and audiology services can be useful afterwards, for instance for further hearing assessment, discussion of salvage options if available, tinnitus support or fitting hearing aids. If you go privately, ask whether the clinic can see you immediately, and make sure your GP is told about any treatment you receive.