While there is no cure, most people with tinnitus get used to it over time; for a minority, it remains a significant problem.

Some over-the-counter as well as prescription drugs and certain industrial chemicals are ototoxic. Exposure to

these can result in temporary or permanent hearing loss.

Some medications cause irreversible damage to the ear, and are limited in their use for this reason. The most important group is the aminoglycosides (main member gentamicin). A rare mitochondrial mutation, m.1555A>G, can increase an individual's susceptibility to the ototoxic effect of aminoglycosides. Long term hydrocodone (Vicodin) abuse is known to cause rapidly progressing sensorineural hearing loss, usually without vestibular symptoms. Methotrexate, a chemotherapy agent, is also known to cause hearing loss. In most cases hearing loss does not recover when the drug is stopped. Paradoxically, methotrexate is also used in the treatment of autoimmune-induced inflammatory hearing loss.

Various other medications may reversibly degrade hearing. This includes loop diuretics, sildenafil (Viagra), high or sustained dosing of NSAIDs (aspirin, ibuprofen, naproxen, and various prescription drugs: celecoxib, etc.), quinine, and macrolide antibiotics (erythromycin, etc.).

Prolonged or repeated environmental or work-related exposure to ototoxic chemicals can also result in sensorineural hearing loss. Some of these chemicals are:

- butyl nitrite - chemical used recreationally known as 'poppers'

- carbon disulfide - a solvent used as a building block in many organic reactions

- styrene, an industrial chemical precursor of polystyrene, a plastic

- carbon monoxide, a poisonous gas resulting from incomplete combustion

- heavy metals: tin, lead, manganese, mercury

- hexane, an industrial solvent and one of the significant constituents of gasoline

- ethylbenzene, an industrial solvent used in the production of styrene

- toluene and xylene, highly poisonous petrochemical solvents. Toluene is a component of high-octane gasolne; xylene is used in the production of polyester fibers and resins.

- trichloroethylene, an industrial degreasing solvent

- Organophosphate pesticides

The aging process has three distinct components: physiologic degeneration, extrinsic damage (nosocusis), and intrinsic damage (sociocusis). These factors are superimposed on a genetic substrate, and may be overshadowed by general age-related susceptibility to diseases and disorders.

Hearing loss is only weakly correlated with age. In preindustrial and non-industrial societies, persons retain their hearing into old age. In the Framingham cohort study, only 10% of the variability of hearing with age could be explained by age-related physiologic deterioration. Within family groups, heredity factors were dominant; across family groups, other, presumably sociocusis and nosocusis factors were dominant.

- Heredity: factors like early aging of the cochlea and susceptibility of the cochlea for drug insults are genetically determined.

- Oxidative stress

- General inflammatory conditions

Nosocusis factors are those that can cause hearing loss, which are not noise-based and separate from pure presbycusis. They may include:

- Ototoxic drugs: Ingestion of ototoxic drugs like aspirin may hasten the process of presbycusis.

- vascular degeneration

- Atherosclerosis: May diminish vascularity of the cochlea, thereby reducing its oxygen supply.

- Dietary habits: Increased intake of saturated fat may accelerate atherosclerotic changes in old age.

- Smoking: Is postulated to accentuate atherosclerotic changes in blood vessels aggravating presbycusis.

- Diabetes: May cause vasculitis and endothelial proliferation in the blood vessels of the cochlea, thereby reducing its blood supply.

- Hypertension: causes potent vascular changes, like reduction in blood supply to the cochlea, thereby aggravating presbycusis.

However, a recent study found that diabetes, atherosclerosis and hypertension had no correlation to presbycusis, suggesting that these are nosocusis (acquired hearing loss) factors, not intrinsic factors.

Most people living in modern society suffer from some degree of progressive sensorineural (i.e. permanent) noise-induced hearing loss (NIHL) resulting from overloading and damaging the sensory or neural apparatus of hearing in the inner ear. NIHL is typically a drop-out or notch centered at 4000 Hz. Both intensity (SPL) and duration of exposure, and repetitive exposure to unsafe levels of noise contribute to cochlear damage that results in hearing loss. The louder the noise is, the shorter the safe amount of exposure is. NIHL can be either permanent or temporary, called a threshold shift.

Unsafe levels of noise can be as little as 70 dB (about twice as loud as normal conversation) if there is prolonged (24-hour) or continuous exposure. 125 dB (loud rock concert ~120 dB) is the pain level; sounds above this level cause instant and permanent ear damage.

Noise and ageing are the primary causes of presbycusis, or age-related hearing loss, the most common kind of hearing loss in industrial society.

Noise-related causes of hearing loss are divided into extrinsic (nosocusis) and intrinsic (sociocusis) causes: In the auditory system, the extrinsic component (nosocusis) includes hearing loss due to otologic disease, hazardous noise exposure, acoustic trauma, and ototoxic agents. The intrinsic component (sociocusis) indicates the wear-and-tear effects of exposure to the everyday sounds of normal living. People who live in nonindustrialized regions avoid both nosocusis and sociocusis and demonstrate excellent hearing into old age.

The dangers of environmental and occupational noise exposure are widely recognized. Numerous national and international organizations have established standards for safe levels of exposure to noise in industry, the environment, military, transportation, agriculture, mining and other areas.

Sound intensity or sound pressure level (SPL) is measured in decibels (dB). For reference,

An increase of 6 dB represents a doubling of the SPL, or energy of the sound wave, and therefore its propensity to cause ear damage. Because our ears hear logarithmically, not linearly, it takes an increase of 10 dB to produce a sound that is perceived to be twice as loud. Ear damage due to noise is proportional to sound intensity (SPL), not perceived loudness, so it's misleading to rely on our subjective perception of loudness as an indication of the risk to hearing, i.e., it can significantly underestimate the danger.

While the standards differ moderately in levels of intensity and duration of exposure considered safe, some guidelines

can be derived.

The safe amount of exposure is reduced by a factor of 2 for every exchange rate (3 dB for NIOSH standard or 5 dB for OSHA standard) increase in SPL. For example, the safe daily exposure amount at 85 dB (90 dB for OSHA) is 8 hours, while the safe exposure at 94 dB(A) (nightclub level) is only 1 hours. Noise trauma can also cause a reversible hearing loss, called a temporary threshold shift. This typically occurs in individuals who are exposed to gunfire or firecrackers, and hear ringing in their ears after the event (tinnitus).

- ambient environmental noise — Populations living near airports, railyards and train stations, freeways and industrial areas are exposed to levels of noise typically in the 65 to 75 dBA range. If lifestyles include significant outdoor or open window conditions, these exposures over time can degrade hearing. U.S. Dept. of Housing and Urban Development sets standards for noise impact in residential and commercial construction zones. HUD’s noise standards may be found in 24 CFR Part 51, Subpart B. Environmental noise above 65 dB defines a noise-impacted area.

- Personal audio electronics, such as iPods (iPods often reaching 115 decibels or higher), can produce powerful enough sound to cause significant NIHL.

- Repeated exposure to loud noise (90-95 dB or more) can cause progressive hearing loss. Sound levels at places where live or dance music is performed typically range from 95 dB to 104 dB.

- acoustic trauma — Exposure to a single event of extremely loud noise (such as explosions) can also cause temporary or permanent hearing loss. A typical source of acoustic trauma is a too-loud music concert.

- workplace noise — OSHA standards 1910.95 General Industry Occupational Noise Exposure, and 1926.52 Construction Industry Occupational Noise Exposure identify the level of 90 dB(A) for 8 hour exposure as the level necessary to protect workers from hearing loss.

Tinnitus is commonly thought of as a symptom of adulthood, and is often overlooked in children. Children with hearing loss have a high incidence of tinnitus, even though they do not express the condition or its effect on their lives. Children do not generally report tinnitus spontaneously and their complaints may not be taken seriously. Among those children who do complain of tinnitus, there is an increased likelihood of associated otological or neurological pathology such as migraine, juvenile Meniere’s disease or chronic suppurative otitis media. Its reported prevalence varies from 12% to 36% in children with normal hearing thresholds and up to 66% in children with a hearing loss and approximately 310% of children have been reported to be troubled by tinnitus.

From 3% to 11% of diagnosed dizziness in neuro-otological clinics are due to Meniere's. The annual incidence rate is estimated to be about 15/100,000 and the prevalence rate is about 218/100,000, and around 15% of people with Meniere's disease are older than 65. In around 9% of cases a relative also had MD, signalling that there may be a genetic predisposition in some cases.

The odds of MD are greater for people of white ethnicity, with severe obesity, and women. Several conditions are often comorbid with MD, including arthritis, psoriasis, gastroesophageal reflux disease, irritable bowel syndrome, and migraine.

Third window effect caused by:

- Superior canal dehiscence – which may require surgical correction.

- Widened vestibular aqueducts

Fluid accumulation is the most common cause of conductive hearing loss in the middle ear, especially in children. Major causes are ear infections or conditions that block the eustachian tube, such as allergies or tumors. Blocking of the eustachian tube leads to decreased pressure in the middle ear relative to the external ear, and this causes decreased motion of both the ossicles and the tympanic membrane.

- acute or serous otitis media

- otitis media with effusion or 'glue ear'

- Perforated eardrum

- Chronic suppurative otitis media (CSOM)

- Cholesteatoma

- Otosclerosis, abnormal growth of bone in or near the middle ear

- middle ear tumour

- ossicular discontinuity as a consequence of infection or temporal bone trauma

- Congenital malformation of the ossicles. This can be an isolated phenomenon or can occur as part of a syndrome where development of the 1st and 2nd branchial arches is seen such as in Goldenhar syndrome, Treacher Collins syndrome, branchio-oto-renal syndrome etc.

- Barotrauma unequal air pressures in the external and middle ear. This can temporarily occur, for example, by the environmental pressure changes as when shifting altitude, or inside a train going into a tunnel. It is managed by any of various methods of ear clearing manoeuvres to equalize the pressures, like swallowing, yawning, or the Valsalva manoeuvre. More severe barotrauma can lead to middle ear fluid or even permanent sensorineural hearing loss.

In one study, the number of new cases of cholesteatoma in Iowa was estimated in 1975–6 to be just under one new case per 10,000 citizens per year. Cholesteatoma affects all age groups, from infants through to the elderly. The peak incidence occurs in the second decade.

Myringosclerosis seems to be more common than tympanosclerosis. Most research has not been conducted upon the general, healthy population, but rather those with otitis media or patients who have had tympanostomy tubes in prior procedures. Of the children studied who had 'glue ear', and who were treated with tympanostomy tubing, 23-40% of cases had tympanosclerosis. One study suggested that people with atherosclerosis were more likely to have tympanosclerosis than otherwise healthy individuals.

About 1 in 1,000 children in the United States is born with profound deafness. By age 9, about 3 in 1,000 children have hearing loss that affects the activities of daily living. More than half of these cases are caused by genetic factors. Most cases of genetic deafness (70% to 80%) are nonsyndromic; the remaining cases are caused by specific genetic syndromes. In adults, the chance of developing hearing loss increases with age; hearing loss affects half of all people older than 80 years.

It may be that a genetic tendency to develop otosclerosis is inherited by some people. Then a trigger, such as a viral infection (like measles), actually causes the condition to develop.

Individuals with Nager syndrome typically have the malformations of the auricle, external auditory canal, and middle ear, including the ossicles. These malformations were found in 80% of individuals with Nager syndrome. Inner ear malformations, however, are not typically seen in this population. Middle ear disease is common among individuals with Nager syndrome. Chronic otitis media and Eustachian tube deformity can result in conductive hearing loss. For this reason, early detection and treatment for middle ear disease is crucial in this population. Sensorineural hearing loss is not a typical characteristic of Nager syndrome; however, a subset of individuals present with a mixed hearing loss, due to a progressive sensorineural component combined with the typical conductive hearing loss (Herrman "et al.", 2005).

Various strategies may be used to manage tympanic membrane retraction, with the aims of preventing or relieving hearing loss and cholesteatoma formation.

It is important that the patient attend periodic follow-up checks, because even after careful microscopic surgical removal, cholesteatomas may recur. Such recurrence may arise many years, or even decades, after treatment.

A "residual cholesteatoma" may develop if the initial surgery failed to completely remove the original; residual cholesteatomas typically become evident within the first few years after the initial surgery.

A "recurrent cholesteatoma" is a new cholesteatoma that develops when the underlying causes of the initial cholesteatoma are still present. Such causes can include, for example, poor eustachian tube function, which results in retraction of the ear drum, and failure of the normal outward migration of skin.

In a retrospective study of 345 patients with middle ear cholesteatoma operated on by the same surgeon, the overall 5-year recurrence rate was 11.8%. In a different study with a mean follow-up period of 7.3 years, the recurrence rate was 12.3%, with the recurrence rate being higher in children than in adults.

As retraction pockets may remain stable or resolve spontaneously, it may be appropriate to observe them for a period of time before considering any active treatment.

In most cases, tympanosclerosis does not cause any recognisable hearing loss up to ten years after the initial disease onset. Sclerotic changes seem to stabilise, but not resolve or dissolve, after 3 years.

These can be both congenital or develop over time with the thinning of the otic capsule by the persistent pulsations of the intracranial pressures against the bones of the skull. Finally, disease conditions—for example cholesteatoma—can result in a labyrinthine fistula. Traumatic events, with excessive pressure changes to the inner ear such as in scuba diving, head trauma, or an extremely loud noise can lead to rupture and leakage.

According to current research, in approximately 2.5% of the general population the bones of the head develop to only 60–70% of their normal thickness in the months following birth. This genetic predisposition may explain why the section of temporal bone separating the superior semicircular canal from the cranial cavity, normally 0.8 mm thick, shows a thickness of only 0.5 mm, making it more fragile and susceptible to damage through physical head trauma or from slow erosion. An explanation for this erosion of the bone has not yet been found.

Ménière's disease usually starts confined to one ear; it appears that it extends to both ears in about 30% of cases.

People may start out with only one symptom, but in MD all three appear with time. Hearing loss usually fluctuates in the beginning stages and becomes more permanent in later stages. MD has a course of 5–15 years, and people generally end up with mild disequilibrium, tinnitus, and moderate hearing loss in one ear.

Once diagnosed, the gap in the temporal bone can be repaired by surgical resurfacing of the affected bone or plugging of the superior semicircular canal. These techniques are performed by accessing the site of the dehiscence either via a middle fossa craniotomy or via a canal drilled through the transmastoid bone behind the affected ear. Bone cement has been the material most often used, in spite of its tendency to slippage and resorption, and a consequent high failure rate; recently, soft tissue grafts have been substituted.

When diagnosing, PLF should be differentiated from Ménière's disease. Tympanostomy has been reported to be a way to diagnose and cure PLF.

The disease can be considered to be hereditary, but its penetrance and the degree of expression is so highly variable that it may be difficult to detect an inheritance pattern. Most of the implicated genes are transmitted in an autosomal dominant fashion. One genome-wide analysis associates otosclerosis with variation in RELN gene.

Loci include:

Otitis media is a particularly common cause of otalgia in early childhood, often occurring secondary to other infectious illnesses, such as colds, coughs, or conjunctivitis.