Embarrassing Illnesses

Most causes of tinnitus are benign (not harmful), and the symptom is most commonly associated with old age. However, tinnitus is starting to affect a growing number of younger people  the general increase in noise levels in today’s society.

Nerve damage

The most common cause of tinnitus is damage to the sensitive hearing nerves inside the inner ear.

Sounds pass from the outer ear, through the middle ear, and on to the inner ear, which contains the cochlea and the auditory nerve. The cochlea is a coiled, spiral tube that contains many sensitive hair cells. The auditory nerve transmits sounds to the brain.

If the tiny nerves inside your ear are damaged, or destroyed, an abnormal stream of impulses is produced that the brain interprets as a sound. These impulses cause the noise that is associated with tinnitus.

In older people, tinnitus is often caused by natural hearing loss (presbyacusis), which lessens the sensitivity of the hearing nerves. In younger people, tinnitus can sometimes occur as a result of hearing damage that is caused by excessive noise.

Other causes

The exact cause of tinnitus cannot always be identified, even after examination by a specialist. However, as well as natural hearing deterioration and hearing damage, there are a number of other possible causes of tinnitus. These include:

• a build up of earwax in the ear that causes it to become blocked,
• a middle ear infection (otitis media),
• glue ear (serous otitis media),
• otosclerosis, a hereditary condition where an abnormal bone growth in the middle ear causes hearing loss,
• Ménière's disease, a condition that affects a part of the inner ear, known as the labyrinth, and causes problems with balance,
• anaemia, where a reduced number of red blood cells causes the blood to become thinner, and to circulate so rapidly that it produces a sound, and
• a perforated eardrum.

Rarer causes

Less commonly, tinnitus may also develop as a result of:

• a head injury,
• exposure to a sudden or very loud noise, such as gunfire or an explosion,
• acoustic neuroma. A rare, benign growth that affects the hearing nerve in the inner ear,
• impacted wisdom teeth, when wisdom teeth have not completely moved into their normal position,
• adverse reactions to certain medications, such as antibiotics, diuretics, aminoglycosides, quinine, and aspirin (this is more likely to occur when the dosage is exceeded),
• solvent abuse, alcohol abuse and other forms of drug abuse,
• high blood pressure and narrowing of the arteries (atherosclerosis), or
• an overactive thyroid gland.

Stress is not a direct cause of tinnitus but it can sometimes make the symptom worse. For example, some people have reported that their tinnitus was worse during stressful events in their life, such as bereavement.