Imagine waking up one morning and suddenly realizing you cannot hear properly from one ear.
Your ear may feel blocked. Sounds may appear distant. You might hear ringing or buzzing.
Many people initially assume it is earwax, congestion, or a temporary ear problem.
Sometimes it is.
But sudden hearing loss in one ear can also be a condition called Sudden Sensorineural Hearing Loss, or SSNHL.
This is very different from a simple blocked ear.
More importantly, treatment can be time-sensitive.
I am Dr. Sandeep Bhasin, and at Care Well Medical Centre, Delhi, we use doctor-supervised Hyperbaric Oxygen Therapy for selected medical conditions.
When patients contact us about sudden hearing loss, my first message is simple:
Do not wait several days hoping the hearing will return on its own. Get the ear evaluated by an ENT specialist as early as possible.
HBOT can play an important role in selected cases. However, it usually works as part of treatment rather than replacing standard ENT care.
Let us understand why.
What Is Sudden Hearing Loss in One Ear?
Sudden hearing loss means that hearing drops rapidly, usually over several hours or a few days.
Doctors become particularly concerned when the problem involves the inner ear or hearing nerve.
This is known as sudden sensorineural hearing loss.
The Undersea and Hyperbaric Medical Society describes idiopathic sudden sensorineural hearing loss as a recognised indication for HBOT. A commonly used medical definition involves a hearing loss of at least 30 decibels across three consecutive frequencies occurring within three days.
For patients, however, the experience is usually much simpler.
You may notice:
- Sudden reduction of hearing in one ear
- A blocked or muffled feeling
- Ringing in the affected ear
- Difficulty understanding speech
- A feeling of fullness inside the ear
- Dizziness or vertigo
- Sounds becoming distorted
- Difficulty locating where sounds are coming from
Sometimes people discover it while answering their phone.
They move the phone from one ear to the other and suddenly realise one ear is hearing very differently.
That should not be ignored.
Is Sudden Hearing Loss an Emergency?
Sudden unexplained hearing loss should be assessed urgently.
There are many harmless reasons why an ear may feel blocked.
Earwax, middle-ear fluid, infection, or pressure changes can all reduce hearing.
But you cannot reliably distinguish these problems from sudden sensorineural hearing loss at home.
An ENT examination and hearing test are important.
The American Academy of Otolaryngology–Head and Neck Surgery recommends audiometric testing as quickly as possible and within 14 days of symptom onset. Treatment decisions should not be unnecessarily delayed while waiting for extensive investigations.
From a practical point of view, I would not advise someone to wait 10 or 14 days.
If your hearing suddenly drops in one ear, try to arrange an ENT assessment as early as possible.
Time matters.
Why Can Hearing Suddenly Disappear?
In many cases, doctors never identify one definite cause.
That is why you may hear the term idiopathic SSNHL.
Several mechanisms have been proposed.
They include:
- Viral inflammation
- Reduced blood supply to the inner ear
- Inflammation around delicate hearing structures
- Autoimmune reactions
- Damage to cochlear hair cells
- Inner-ear membrane problems
- Microcirculation disturbances
The cochlea is a tiny structure inside your inner ear.
Inside it are extremely delicate sensory cells that convert sound vibrations into electrical signals.
Your brain then interprets these signals as sound.
These cells have a high metabolic requirement and depend on a continuous supply of oxygen.
When oxygen delivery becomes compromised, even temporarily, these sensitive structures may suffer.
This is one reason Hyperbaric Oxygen Therapy has attracted significant interest in sudden hearing loss.
What Is HBOT Therapy for Sudden Hearing Loss?
Hyperbaric Oxygen Therapy, or HBOT, involves breathing medical-grade oxygen inside a pressurised chamber.
Pressure changes the way oxygen travels through the body.
Normally, most oxygen is carried by haemoglobin inside red blood cells.
Inside a hyperbaric chamber, increased pressure allows considerably more oxygen to dissolve directly into the blood plasma.
That oxygen can then reach areas where normal circulation may be compromised.
At Care Well Medical Centre, HBOT is performed under medical supervision with a personalised treatment plan after clinical assessment.
You can read more about our doctor-supervised approach here:
Hyperbaric Oxygen Therapy in Delhi at Care Well Medical Centre
How Can HBOT Help Sudden Hearing Loss?
To understand this, imagine the cochlea as a tiny organ working continuously throughout your life.
Its sensory cells need oxygen.
If inflammation or impaired microcirculation reduces oxygen availability, the inner ear may become stressed.
HBOT dramatically increases oxygen availability in the blood.
The aim is to increase oxygen reaching the cochlea and surrounding inner-ear structures.
This may potentially:
- Improve oxygen delivery to the inner ear
- Support stressed cochlear cells
- Reduce tissue hypoxia
- Support cellular recovery
- Complement the effects of steroid treatment
HBOT is therefore not simply about "giving more oxygen."
It is oxygen delivered under controlled pressure.
That difference is important.
Can HBOT Restore Hearing Completely?
HBOT may improve the chances of hearing recovery in appropriately selected patients.
However, no responsible doctor should promise complete hearing restoration.
Several factors influence recovery.
These include:
- How severe the initial hearing loss is
- How quickly treatment begins
- Patient age
- Presence of vertigo
- Which frequencies are affected
- Overall inner-ear damage
- Response to steroids
- Underlying medical conditions
- Delay before starting treatment
Some patients recover substantially.
Some recover partially.
Others may unfortunately have little improvement despite appropriate treatment.
The goal is therefore to give the inner ear the best possible opportunity to recover during the available treatment window.
What Does Research Say About HBOT for Sudden Hearing Loss?
The evidence has become increasingly interesting.
A 2025 systematic review and meta-analysis examined 20 studies involving more than 1,600 patients.
Patients receiving HBOT combined with medical therapy had higher odds of hearing recovery compared with medical treatment alone.
The researchers calculated approximately 2.6 times higher odds of hearing recovery in the combined HBOT group.
However, the authors also highlighted variations between treatment protocols and called for further standardised research.
An earlier systematic review of prospective randomised studies also found better hearing improvement when HBOT was included in treatment.
At the same time, not every published review reaches equally strong conclusions.
A 2024 umbrella review found an overall benefit but noted that the quality of evidence varied considerably between studies.
This is why I prefer explaining HBOT realistically.
HBOT has evidence supporting its use in SSNHL, particularly when combined with appropriate medical treatment. It is not a guaranteed hearing-restoration treatment.
When Should HBOT Be Started After Sudden Hearing Loss?
This may be the most important section of this article.
Earlier treatment generally gives us the greatest opportunity to help.
Current American Academy of Otolaryngology guidance states that clinicians may offer:
- HBOT combined with steroids within two weeks of SSNHL onset.
- HBOT combined with steroids as salvage treatment within one month of onset.
The Undersea and Hyperbaric Medical Society also reports the best outcomes when HBOT and corticosteroid treatment are started early, particularly within approximately 14 days.
That does not mean somebody on day 15 should give up.
It means do not knowingly waste the early treatment window.
Are Steroids or HBOT More Important?
This should not usually be viewed as an either-or decision.
For appropriately selected patients, the two treatments may complement each other.
Corticosteroids are widely used in sudden sensorineural hearing loss.
Depending upon the patient's circumstances, an ENT specialist may consider:
- Oral or intravenous corticosteroids
- Intratympanic steroid injections
- HBOT alongside steroid treatment
The AAO-HNS guideline allows corticosteroids as initial treatment within two weeks.
For patients with incomplete recovery, intratympanic steroid treatment is recommended as salvage therapy approximately two to six weeks after onset.
HBOT therefore generally forms part of a combined treatment strategy rather than replacing ENT treatment.
Care Well Medical Centre Protocol for Sudden Hearing Loss and HBOT
At Care Well Medical Centre, I prefer a structured and medically supervised approach.
We do not recommend somebody simply enter an HBOT chamber because one ear feels blocked.
We first need to know what we are treating.
Step 1: Confirm the Diagnosis
An ENT evaluation is important.
The doctor needs to determine whether the hearing loss is:
Conductive hearing loss
This may result from earwax, middle-ear fluid, infection, or another mechanical problem.
Or:
Sensorineural hearing loss
This involves the inner ear or hearing pathway and requires a different approach.
Pure-tone audiometry helps measure the type and severity of hearing loss.
Step 2: Do Not Delay Standard ENT Treatment
If sudden sensorineural hearing loss is confirmed, HBOT should not delay steroid treatment.
The patient's ENT specialist decides whether systemic steroids, intratympanic steroids, or both are appropriate.
HBOT then works as an adjunctive therapy.
Step 3: Medical Screening Before HBOT
Before starting Hyperbaric Oxygen Therapy at Care Well Medical Centre, we review:
- Medical history
- Current medications
- Lung health
- Ear and sinus condition
- Blood pressure
- Relevant medical illnesses
- Ability to equalise ear pressure
- Any contraindications to HBOT
Our existing HBOT programme uses doctor-led planning rather than technician-only treatment.
We also pay particular attention to ear pressure because the patient already has an ear-related condition.
Step 4: Individualise Chamber Pressure and Duration
Evidence-based SSNHL protocols commonly use approximately:
2.0 to 2.5 ATA pressure
with around:
90 minutes of treatment
per session.
Published UHMS guidance describes treatment in this general range, commonly over 10 to 20 sessions.
At Care Well Medical Centre, patients with sudden hearing loss may commonly be planned for minimum 20 or above sessions, depending on:
- Severity of hearing loss
- Time since onset
- Audiogram findings
- Clinical response
- ENT recommendations
- Patient tolerance
The protocol is not identical for every patient.
Step 5: Monitor Hearing Recovery
We should not judge treatment only by asking:
"Does your ear feel better?"
