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Sudden Hearing Loss


Lawrence R. Lustig

, MD, Columbia University Medical Center and New York Presbyterian Hospital

Reviewed/Revised Jul 2022
Topic Resources

General reference

Etiology of Sudden Hearing Loss

The following are common characteristics of sudden hearing loss:

  • Most cases are idiopathic (see table ).

  • Some occur in the course of an obvious explanatory event.

  • A few represent the initial manifestation of another, initially occult, but identifiable disorder.


There are numerous theories for which some evidence (although conflicting and incomplete) exists. The most promising possibilities include viral infections (particularly involving herpes simplex Overview of Herpesvirus Infections Eight types of herpesviruses infect humans (see table ). After initial infection, all herpesviruses remain latent within specific host cells and may subsequently reactivate. Clinical syndromes... read more ), autoimmune attacks, and acute microvascular occlusion.

Obvious event

Some causes of sudden hearing loss are readily apparent.

Blunt head trauma with temporal bone fracture or severe concussion involving the cochlea can cause sudden hearing loss.

Large ambient pressure changes Ear and Sinus Barotrauma Barotrauma is tissue injury caused by a pressure-related change in body compartment gas volume. It can affect the ear (causing ear pain, hearing loss, and/or vestibular symptoms) or the sinuses... read more (eg, caused by diving) or strenuous activities (eg, weightlifting) can induce a perilymphatic fistula between the middle and inner ear, causing sudden, severe symptoms. Perilymphatic fistula can also be congenital; it can spontaneously cause a sudden loss or loss may occur after trauma or severe pressure changes.

Ototoxic drugs Drug-Induced Ototoxicity A wide variety of drugs can be ototoxic. Medication-related factors affecting ototoxicity include Dose Duration of therapy Concurrent renal failure Infusion rate read more can result in hearing loss occurring sometimes within a day, especially with an overdose (systemically or when applied to a large wound area, such as a burn). There is a rare genetic mitochondrial-transmitted disorder that increases the susceptibility to aminoglycoside ototoxicity.

A number of infections cause sudden hearing loss during or immediately after acute illness. Common causes include bacterial meningitis Acute Bacterial Meningitis Acute bacterial meningitis is rapidly progressive bacterial infection of the meninges and subarachnoid space. Findings typically include headache, fever, and nuchal rigidity. Diagnosis is by... read more , Lyme disease Lyme Disease Lyme disease is a tick-transmitted infection caused by the spirochete Borrelia species. Early symptoms include an erythema migrans rash, which may be followed weeks to months later by... read more Lyme Disease , and many viral infections that affect the cochlea (and sometimes the vestibular apparatus). The most common viral causes in the developed world are mumps Mumps Mumps is an acute, contagious, systemic viral disease, usually causing painful enlargement of the salivary glands, most commonly the parotids. Complications may include orchitis, meningoencephalitis... read more Mumps and herpes simplex Overview of Herpesvirus Infections Eight types of herpesviruses infect humans (see table ). After initial infection, all herpesviruses remain latent within specific host cells and may subsequently reactivate. Clinical syndromes... read more . Measles Measles Measles is a highly contagious viral infection that is most common among children. It is characterized by fever, cough, coryza, conjunctivitis, an enanthem (Koplik spots) on the oral mucosa... read more Measles is a very rare cause because most of the population is immunized.

Other disorders

Cogan syndrome Cogan Syndrome Cogan syndrome is a rare autoimmune disease involving the eye and the inner ear. Cogan syndrome affects young adults, with 80% of patients between 14 and 47 years. The disease appears to result... read more is a rare autoimmune reaction directed against an unknown common autoantigen in the cornea and inner ear; > 50% of patients present with vestibuloauditory symptoms. About 10 to 30% of patients also have a severe systemic vasculitis, which may include life-threatening aortitis.


Evaluation of Sudden Hearing Loss

Evaluation consists of detecting and quantifying hearing loss and determining etiology (particularly reversible causes).


History of present illness should verify that loss is sudden and not chronic. The history should also note whether loss is unilateral or bilateral and whether there is a current acute event (eg, head injury, barotrauma Otic Barotrauma Otic barotrauma is ear pain or damage to the tympanic membrane caused by rapid changes in environmental pressure. To maintain equal pressure on both sides of the tympanic membrane, gas must... read more [particularly a diving injury], infectious illness). Important accompanying symptoms include other otologic symptoms (eg, tinnitus, ear discharge), vestibular symptoms (eg, disorientation in the dark, vertigo), and other neurologic symptoms (eg, headache, weakness or asymmetry of the face, abnormal sense of taste).

Past medical history should ask about known HIV or syphilis infection and risk factors for them (eg, multiple sex partners, unprotected intercourse). Family history should note close relatives with hearing loss (suggesting a congenital fistula). Drug history should specifically query current or previous use of ototoxic drugs Drug-Induced Ototoxicity A wide variety of drugs can be ototoxic. Medication-related factors affecting ototoxicity include Dose Duration of therapy Concurrent renal failure Infusion rate read more and whether the patient has known renal insufficiency or renal failure.

Physical examination

The examination focuses on the ears and hearing and on the neurologic examination.

The tympanic membrane is inspected for perforation, drainage, or other lesions. During the neurologic examination, attention should be paid to the cranial nerves (particularly the 5th, 7th, and 8th) and to vestibular and cerebellar function because abnormalities in these areas often occur with tumors of the brain stem and cerebellopontine angle.

The Weber Physical examination Physical examination and Rinne Physical examination Physical examination tests require a tuning fork to differentiate conductive from sensorineural hearing loss.

Red flags

Findings of particular concern are

  • Abnormalities of cranial nerves (other than hearing loss)

  • Significant asymmetry in speech understanding between the 2 ears

  • Other neurologic symptoms and signs (eg, motor weakness, aphasia, Horner syndrome, sensory or temperature sensation abnormalities)

Interpretation of findings

Traumatic, ototoxic, and some infectious causes are usually apparent clinically. A patient with perilymphatic fistula may hear an explosive sound in the affected ear when the fistula occurs and may also have sudden vertigo, nystagmus, and tinnitus.

Focal neurologic abnormalities are of particular concern. The 5th cranial nerve, 7th cranial nerve, or both are often affected by tumors that involve the 8th cranial nerve, so loss of facial sensation and weak jaw clench (5th) and hemifacial weakness and taste abnormalities (7th) point to a lesion in that area.

Fluctuating unilateral hearing loss accompanied by aural fullness, tinnitus, and vertigo also suggests Meniere syndrome Meniere Disease Meniere disease is an inner ear disorder that causes vertigo, nausea, fluctuating sensorineural hearing loss, and tinnitus. There is no reliable diagnostic test. Vertigo and nausea are treated... read more . Systemic symptoms suggesting inflammation (eg, fevers, rash, joint pains, mucosal lesions) should raise suspicion of an occult infection or autoimmune disorder.


Patients should have an audiogram, and unless the diagnosis is clearly an acute infection or drug toxicity, most clinicians do gadolinium-enhanced MRI to diagnose inapparent causes, particularly for unilateral losses. Patients with an acute traumatic cause also should have MRI. A perilymphatic fistula is typically suspected from an inciting event (eg, excessive strain, barotrauma), and testing may be done by using positive pneumatic pressure to evoke eye movements (nystagmus). CT of the temporal bones is usually done to show the bony characteristics of the inner ear and can help elucidate congenital abnormalities (eg, enlarged vestibular aqueduct), fractures of the temporal bone from trauma, or erosive processes (eg, cholesteatoma).

Patients who have risk factors for or symptoms that suggest causes should have appropriate tests based on clinical evaluation (eg, serologic tests for possible HIV infection or syphilis, complete blood count [CBC] and coagulation profile for hematologic disorders, erythrocyte sedimentation rate [ESR] and antinuclear antibodies for vasculitis).

Treatment of Sudden Hearing Loss

Treatment of sudden hearing loss focuses on the causative disorder when known. Fistulas are explored and repaired surgically when bed rest fails to control symptoms.

In viral and idiopathic cases, hearing returns to normal in about 50% of patients and is partially recovered in others.

In patients who recover their hearing, improvement usually occurs within 10 to 14 days.

Recovery from an ototoxic drug varies greatly depending on the drug and its dosage. With some drugs (eg, aspirin, diuretics), hearing loss resolves within 24 hours, whereas other drugs (eg, antibiotics, chemotherapy drugs) often cause permanent hearing loss if safe dosages have been exceeded.

For patients with idiopathic loss, many clinicians empirically give a course of glucocorticoids (typically prednisone 60 mg orally once a day for 7 to 14 days followed by a 5 day taper). Glucocorticoids can be given orally and/or by transtympanic injection. Direct transtympanic injection avoids the systemic side effects of oral glucocorticoids and appears equally effective except in profound (> 90 decibels) hearing loss. There are data showing that using both oral and intratympanic steroids leads to better outcomes than either alone. Although clinicians often give antiviral drugs effective against herpes simplex (eg, valacyclovir, famciclovir), data show that such drugs do not affect hearing outcomes. There are some limited data suggesting that hyperbaric oxygen therapy may be beneficial in idiopathic sudden hearing loss.

Key Points

  • Most cases of sudden hearing loss are idiopathic.

  • A few cases have an obvious cause (eg, major trauma, acute infection, drugs).

  • A very few cases represent unusual manifestations of treatable disorders.

  • Evaluation includes audiometry, CT and MRI, and other tests for suspected causes.

  • Treatment focuses on known causes, and corticosteroids are given in cases of idiopathic sudden hearing loss.

Drugs Mentioned In This Article

Drug Name Select Trade
Anacin Adult Low Strength, Aspergum, Aspir-Low, Aspirtab , Aspir-Trin , Bayer Advanced Aspirin, Bayer Aspirin, Bayer Aspirin Extra Strength, Bayer Aspirin Plus, Bayer Aspirin Regimen, Bayer Children's Aspirin, Bayer Extra Strength, Bayer Extra Strength Plus, Bayer Genuine Aspirin, Bayer Low Dose Aspirin Regimen, Bayer Womens Aspirin , BeneHealth Aspirin, Bufferin, Bufferin Extra Strength, Bufferin Low Dose, DURLAZA, Easprin , Ecotrin, Ecotrin Low Strength, Genacote, Halfprin, MiniPrin, St. Joseph Adult Low Strength, St. Joseph Aspirin, VAZALORE, Zero Order Release Aspirin, ZORprin
Deltasone, Predone, RAYOS, Sterapred, Sterapred DS
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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