Tinnitus is the perception of noise in the ear or head, which is generated inside the body rather than coming from outside. Tinnitus is usually only heard by the person with the condition, but in a very few rare cases it can also be heard by other people. Temporary tinnitus is common if you have a cold, after exposure to loud noise such as at a music concert, or following a blow to the head. About 1 in 100 people experience serious problems with long-term, established tinnitus. The sounds can be heard in one ear, both ears, or can appear to come from the middle of the head. The condition is more common in older people, but it can occur at any age, even in quite young children. It often gets worse at quiet times, such as when you are trying to get to sleep. This is because there is less background noise to mask or distract you from the sounds associated with tinnitus. Tinnitus may also be more noticeable when you are tired. It is estimated that around 10% of the population are affected by some degree of tinnitus. For most people it is an irritation they learn to live with, but for others it can lead to poor concentration, difficulty in sleeping and depression.
Tinnitus is a symptom, not a condition. Nearly all the causes of tinnitus are benign (not harmful), and it is most commonly associated with old age. However, tinnitus is starting to affect a growing number of young people due to the general increase in sound and noise in today’s society. The sounds heard by people with tinnitus vary but include intermittent or continuous ringing, hissing, whistling, roaring or buzzing noises. About 25% of people with tinnitus experience a pure musical tone, with 75% describing it as a hissing, buzzing or ringing experience. None of the sounds of tinnitus originate from an external source. Some people with tinnitus are also more sensitive to normal everyday sounds. For example, some people with tinnitus find that a radio or TV is painfully loud when it is at a normal volume for most people.
The most common cause of tinnitus is damage to the hearing nerves in the ear (cochlea or inner ear). We hear things through a stream of nerve impulses going from the cochlea to the auditory system in the brain. If the tiny nerves in the ear are damaged or destroyed, this produces an abnormal stream of impulses, which the brain interprets as a sound. This causes the noise associated with tinnitus. Tinnitus in older people is usually caused by natural hearing loss (presbyacusis), which lessens the sensitivity of hearing nerves. In younger people it is most often caused by damage to hearing as a result of excessive noise. However, there are a number of other causes of tinnitus. It is not always possible to identify the exact cause even after examination by a specialist. Other common causes include:
- excessive wax in the ear causing it to become blocked
- middle ear infection (otitis media) or glue ear (serous otitis media);
- otosclerosis (stiffening of the tiny bones which transmit sound from the eardrum to the sound-detecting organ, the cochlea);
- Ménière's disease (a condition causing problems with balance)
- anaemia (in which the thinner blood circulates so rapidly it produces sound); and
- pierced eardrum.
- Less commonly, tinnitus may also develop as a result of:
- exposure to sudden or very loud noise (e.g. gunfire, explosion),
- a head injury,
- the presence of an acoustic neuroma (a rare, benign growth that affects the hearing nerve in the inner ear),
- impacted wisdom teeth (when wisdom teeth haven’t completely moved into the normal position),
- adverse reactions to certain drugs such as antibiotics, diuretics, aminoglycosides, quinine and aspirin, (this is more likely when the dosage is exceeded), and also allergic reactions,
- solvent abuse, alcohol abuse and other drug abuse,
- high blood pressure and narrowing of the arteries (atherosclerosis), and
- overactive thyroid gland.
Tinnitus is rarely a symptom of a more serious problem but there can be other causes such as tumours, spasm, and abnormal blood flow. Some people relate their tinnitus to stressful events in their life, such as bereavement.
Referral by your GP to an otolaryngologist (a specialist doctor for ear disorders) at an ear, nose and throat (ENT) department is often necessary to rule out any underlying cause and to accurately diagnose tinnitus. Your medical history will be looked at, and a number of tests may be carried out, including x-ray of the ear, balance testing, blood test, hearing test, and sometimes a CT (computerised tomography) or MRI (magnetic resonance imaging) scan.
Treatment may be quite different in each case of tinnitus. In most cases there is no cure, and treatment is designed to help people manage tinnitus on a day-to-day basis. Some people find that taking certain medicines can trigger tinnitus. If this is the case, your GP may advise changing medication to stop the tinnitus. Sometimes tinnitus disappears of its own accord, or may only occur in response to an obvious cause such as anxiety or stress. There is no specific medicine to treat tinnitus, but research continues. Tinnitus is strongly linked to stress, and sometimes people are prescribed sedatives, tranquillisers, or antidepressants to help lessen the effect that the tinnitus has on their lives. Normally these are more effective if prescribed together with on- going counselling. Other medicines, such as local anaesthetics, those that interfere with nerve conduction, and anticonvulsants (drugs used to prevent seizures and convulsions), for example, carbamazepine, have been tried to treat the symptoms of tinnitus. However trials have been disappointing. Four randomized clinical trials of carbamazepine and trials of other anticonvulsants have failed to show any benefit.
There are a number of other things that may prove effective in controlling tinnitus:
- listening to calming music on personal headphones especially at bedtime;
- white noise generators, (tinnitus maskers) may make it less easy to hear the tinnitus;
- use of a hearing aid if you have slight hearing loss. Being able to hear sounds you are not cannot normally hear may help to override the tinnitus noise;
- deliberate effort to concentrate on something else and to ignore the tinnitus; and
- cognitive behaviour therapy by a hearing therapist to help people to change their response and lower their awareness of tinnitus.
- Depression is not uncommon with severe tinnitus, and requires specific treatment such as antidepressant drugs or talking therapies such as counselling or cognitive behavioural therapy (CBT).