Start · Catalogue · Profile · Table
Hearing BODY HANDBOOK
Hearing · §49
Sudden Hearing Loss
One morning the world sounds wrong in one ear. Muffled, full, like a bad earplug. If it doesn't pass in a few hours, this is the medical emergency almost nobody recognises as one: sudden sensorineural hearing loss. There is a roughly two-week window in which oral steroids can save the ear. Past it, the loss is usually permanent. The catch is that the symptom is easy to mistake for wax, a cold, or congestion, and most people lose the window because they wait.
Respond · As-needed Evidence Moderate Chapter Hearing

If you get to a doctor inside two weeks, a cheap course of generic steroids gives you the best shot at full recovery; past four to six weeks, the ear you have is the ear you keep. The action is once-only and small: go to the emergency department or a same-day ENT. The stakes are large: a permanent dead ear comes with chronic tinnitus, harder hearing in noise, and the slow downstream cost of depression and cognitive load that single-sided deafness carries.

The inner ear is unusually fragile. The hair cells that turn vibrations into nerve signals don't grow back, and they sit downstream of a single small artery with no backup supply. When anything goes wrong — a virus reactivating in the hearing nerve, a clot in that artery, the immune system attacking the inner ear by mistake — the damage starts on a clock. Days of inflammation that nobody treats become weeks of dead hair cells nobody can bring back.

In more than nine out of ten cases, no one ever finds the cause, which is why doctors call it "idiopathic." That sounds like an excuse but it shapes the treatment logic: rather than wait to know which of four mechanisms is at work, the guideline tells doctors to throw a high-dose steroid course at the inflammation, because that single drug covers most of the plausible causes well enough Chandrasekhar et al. 2019.

What the trial actually showed

About 27 in every 100,000 adults in the United States get this every year, climbing to 77 in people over 65 — far more common than the older textbooks suggested Alexander & Harris 2013. Without treatment, about two-thirds of people recover most of their hearing on their own, usually inside two weeks Mattox & Simmons 1977. That sounds reassuring until you reverse it: one in three are left with a permanently dead ear if no one acts, and the people who recover spontaneously do so almost always in the same window in which steroids work.

How much hearing comes back depends a lot on how much was lost. Mild and moderate drops, especially ones that mostly affect low pitches, recover well most of the time. Severe and profound losses — particularly when the high frequencies go — recover badly, often not at all. If the room spins at the same time the hearing goes, that's a worse signal too.

Why most people miss it

The symptom announces itself badly. It doesn't feel like "I am going deaf in this ear." It feels like the ear is plugged, full, underwater. Voices sound wrong. There's often a ringing or hissing. The natural reaction is to suspect wax, a sinus thing, a cold draining funny, or the after-effects of a flight. So people wait a day. Then two. Then they call their primary care office, who may book them next week. Then they try the drugstore wax-removal kit. By the time someone runs a hearing test, the window is closing or gone.

A second trap: the "most people get better on their own" statistic, which is true and dangerous. It means that for two-thirds of people who never do anything, the ear comes back. It also means that for the other third, the ear stays dead forever, and you cannot tell at the start which group you are in. The only way to take the favourable side of that coin is to treat as if you are in the unlucky third Chandrasekhar et al. 2019.

The bedside test that separates "blocked ear" from "dead ear" takes thirty seconds and a tuning fork. Hum, or put a vibrating fork on the middle of your forehead: if the sound goes to your good ear, that's the bad sign — the nerve in the other ear isn't carrying. If it goes to the muffled ear, it's probably just wax or fluid. Most ER doctors and all ENTs know this test. The trouble is getting in front of one.

What happens if you wait

The first week, the odds are with you. Most people who get steroids in the first seven days and have a recoverable loss to begin with get most of their hearing back. By the end of the second week the door is closing; the trial that established the protocol stopped enrolling people at fourteen days for a reason Rauch et al. 2011. Past four to six weeks, the ear is the ear. There are salvage attempts — steroid injections through the eardrum, hyperbaric oxygen — but the returns are smaller and the ceiling is lower Chandrasekhar et al. 2019.

The forecast for a permanent unilateral loss isn't dramatic at first. The first month you adjust: you keep your good ear toward the speaker, you ask people to repeat themselves more often, you stop trying to figure out where a siren is coming from on the street. By the end of the first year you've quietly stopped going to certain restaurants. Group dinners feel like work. Calls on the dead-ear side stop happening; you switch the phone to the other hand without thinking. A persistent ringing in the dead ear keeps you company — tinnitus is the standard package, and there is no off switch.

A decade in, what longitudinal studies of chronic hearing loss find is the social and cognitive cost. People with untreated hearing loss withdraw earlier, get depressed at higher rates, and show faster cognitive decline than peers with intact hearing. The mechanism is partly the load of straining to listen all day; partly the gradual thinning of social contact when conversations get exhausting. The choice the morning you noticed the muffled ear was, looked at honestly, the choice between a 24-hour inconvenience and that decade.

What to do, in order

If one ear has been notably worse than the other for more than a few hours and it isn't hurting, isn't leaking, and isn't obviously just wax, treat it as an emergency. Today, not Monday.

Do not skip the audiogram. Do not accept "it's probably congestion, give it a week" without one. The audiogram is what tells the doctor whether the loss is the nerve (treat now) or the eardrum and middle ear (no rush, often self-resolving).

When the pills are the wrong route

None of these are reasons to skip treatment. They are reasons to pick the other route.

What recovery actually looks like

If you make it in within the first week and the loss is in the recoverable range, the realistic outcome — depending on how bad the initial drop was — is some-to-most of the hearing comes back over the next few weeks, and the ear settles. The ringing fades for many people, though not all. By the end of the steroid course you can usually tell which way it's going.

What you avoid is the slow set of accommodations the "stakes" section walks through. You keep being able to follow a conversation at the end of a noisy restaurant table. You keep being the person friends call rather than the person who's slow to respond. You keep the side of the room you used to ignore. That sounds small — until you talk to anyone who has the other version.

The thing the protocol cannot promise is full recovery for the unlucky cases. Profound loss, especially with vertigo at the start, often comes back only partially regardless of how fast anyone moves. The point of the protocol is not certainty; it is access to the best probability that's available, and a clean conscience about the outcome.

Where this goes wrong in practice

The classic failure is presenting too late. The second classic failure is presenting to the wrong place. Urgent care often does not have an audiometer and the clinician may not run a tuning-fork test confidently — some will refer you to ENT for a week from Tuesday, which is the entire window gone. If the urgent-care clinic can't confirm with audiometry and start steroids the same day, go to the ER instead.

The third failure is the doctor who takes the symptom at face value and treats for an ear infection or wax. If you have been told it's wax and removing the wax hasn't fixed it within a day, that diagnosis was wrong and the clock is still running. Push for an audiogram and an ENT.

The fourth failure is taking the prednisone for three days, feeling better, and stopping. Half a course is half a treatment. Finish the taper.

What this entry doesn't cover

Gradual age-related hearing loss, loss from years of loud noise, hearing changes from ototoxic medications, conductive losses from middle-ear problems, and Meniere's disease all sit next to this topic but follow different timelines and different rules. Chronic tinnitus once the window has closed is a separate body of evidence and a separate set of options. So is unilateral hearing aid use, CROS devices, and cochlear implants for the cases where recovery doesn't come.

Related in the handbook
Related
  • — The reason people miss the window is mistaking this for wax — but wax builds slowly and doesn't strike overnight.
  • — Before chasing other causes of a sudden drop, check whether a new medication could be the culprit.
  • — Same logic, different sense: sudden loss in one eye or ear is an emergency where hours decide the outcome.
  • — A permanent dead ear usually comes with chronic ringing — one more reason to act inside the two-week window.
  • — Different problem entirely: this is a sudden, treatable drop, not the subtle in-noise difficulty that tests miss.
  • — Age-related loss creeps in over years; this strikes one ear in hours and is a steroid-window emergency.
·
49