Tinnitus is to hear sounds even when everything is quiet. These sounds vary, examples are buzzing or whistling, and can be heard every now and then (intermittently) or continuously. The noise seems to come from inside the ears or within the head. The sounds may be trivial or become distressing.

Most people with hearing loss experience tinnitus, particularly when they have been exposed to excessive noise such as explosions, gunfire, occupational noise, or loud music in the past. Some antibiotics and chemotherapy drugs cause tinnitus. People with poor blood flow to the brain (cerebral insufficiency) often experience a number of problems including tinnitus. These might be difficulties concentrating; loss of memory; confusion; lack of energy; tiredness; reduced physical performance; depressive mood; anxiety; dizziness; and headache.

When symptoms are severe, tinnitus can result in major depression, anxiety and other psychological disturbances, which leads to a progressive deterioration of quality of life.

Tinnitus can neither be heard by others nor measured directly. A variety of drugs and therapies such as changing mood with antidepressants or anti-anxiety drugs, psychotherapy, retraining to ignore the sounds, maskers (white noise generators), biofeedback, acupuncture and hypnotherapy are tried as treatments.

We present some of the evidence from Cochrane systematic reviews about complementary and alternative treatments related to tinnitus. This evidence comes from carefully researched reviews of information about clinical trials done to evaluate medical treatments. Studies are only included in these reviews if they meet pre-defined criteria.

GINKGO BILOBA FOR TINNITUS

Ginkgo biloba is used to improve blood flow to the brain (as in cerebral insufficiency) and improves cognitive functioning. The rationale for using Gingko for tinnitus is that the improved blood circulation may help a person adjust to the noises (habituation).

The most commonly reported side effects with Ginkgo biloba are mild stomach and intestinal problems such as constipation, indigestion and diarrhoea, and headaches. Serious side effects are rare but include excessive bleeding problems. People who are already taking anticoagulant and antiplatelet medications to prevent strokes and heart attacks should consult a doctor before taking Gingko biloba. People who have fits (seizures) are also advised to seek medical advice about using this herb. 

What the synthesised research says

Ginkgo biloba did not help people whose main health problem was tinnitus – after 6 to 12 weeks of treatment.

How it was tested

The researchers made a thorough search of the medical literature to find randomized trials comparing Ginkgo biloba with a dummy or non-active treatment (placebo). They found six trials of people whose primary complaint was tinnitus; in a further six trials people had symptoms of cerebral insufficiency that included tinnitus.

Two trials gave results that could be included in the review. These trials randomly assigned people with tinnitus as the main complaint to receive Gingko biloba or non-active treatment. Doses were in the range 120 to 200 mg daily and treatment was for around 6 to 12 weeks. The trials did not demonstrate any benefit from taking Ginkgo biloba.

Side effects and general cautions

In the one study that actively questioned about possible side effects there was no difference between Ginkgo and non-active treatment.

Source

Hilton M, Stuart E. Ginkgo biloba for tinnitus. The Cochrane Database of Systematic Reviews 2004, Issue 2. Art. No.: CD003852. DOI: 10.1002/14651858.CD003852.pub2.

HYPERBARIC OXYGEN FOR SUDDEN HEARING LOSS AND TINNITUS

Some people experience sudden unexplained hearing loss over 72 hours or less. This happens with or without abnormal persistent noises (tinnitus). The hearing loss can be permanent, although the rate of spontaneous recovery is high. Treatments include vasodilators, plasma volume expanders, steroids, anticoagulants, diuretics, and antivirals. Tinnitus is the perception of sound that can neither be heard by others nor measured directly. It apparently arises from within the ears or the head and may be continuous or intermittent. Often tinnitus is linked with some degree of hearing loss.

What is known

Exposing people to high pressure (hyperbaric) oxygen is based on the argument that both the hearing loss and tinnitus may be caused by a lack of oxygen in parts of the ear (the cochlear apparatus). Hyperbaric oxygen therapy could reverse the oxygen deficit by increasing the supply of oxygen to the inner ear and also the brain and so reduce the severity of hearing loss and tinnitus.

Some people may feel claustrophobic during treatment. Hyperbaric oxygen therapy is associated with some risk of oxygen poisoning. Other possible adverse effects include temporary worsening of short-sightedness and damage to the ears, sinuses and lungs because of the high pressure used. Serious adverse events are rare

What the synthesised research says

For people with recent, sudden hearing loss hyperbaric oxygen therapy did increase the proportion of people with more than 25% improvement in hearing assessment over four frequencies. Hyperbaric oxygen did not lead to a greater number of people with 50% or more improvement. The clinical significance of any improvement is not clear and the routine use of hyperbaric oxygen therapy is not justified from this review.

People who had chronic hearing loss with or without tinnitus did not have any clear improvements in hearing or tinnitus. This conclusion was from a single study in people who had had a loss of hearing for at least six months.  

How it was tested

The researchers made a thorough search of the medical literature and found six authoritative randomised controlled trials. The included trials (with 304 participants) were published between 1995 and 2004.

The conclusions on sudden hearing loss were from two trials involving 114 people. For a 25% increase in hearing threshold over four frequencies, over half (56%) of the people on sham therapy achieved this outcome versus three quarters (78%) on active hyperbaric oxygen therapy; the number-needed-to-treat (NNT) for one extra person to achieve a good outcome with hyperbaric oxygen therapy was 5 (95% CI 3 to 20).

Three trial trials involving 132 participants reported on mean hearing improvement over all frequencies. Two trials suggested mean improvement following hyperbaric oxygen therapy; and one recent trial (54 participants) found there was a significant improvement in those participants with severe or moderate hearing loss at enrolment, but not for those participants with mild hearing loss.

Relief of tinnitus

Acute Tinnitus: Two trials (53 people with recently developed tinnitus) gave measures of a tinnitus score. Both trials reported a greater improvement in tinnitus (using a visual analogue scale between 0 and 10) with hyperbaric oxygen therapy than without.

Chronic Tinnitus: Hyperbaric oxygen therapy did not benefit people with chronic tinnitus compared to a control group. This conclusion was from one trial involving 44 people.

Side effects and general cautions

None of the trials systematically reported adverse effects with hyperbaric oxygen or control therapies. Hyperbaric oxygen therapy should not, however, be considered as a complementary or alternative therapy.

Criteria for a person to be able to participate in a trial varied between the trials and were often poorly reported. This meant that people could have very different degrees of hearing loss and tinnitus (and respond differently to therapy).

The trials were small.

Source

Bennett MH, Kertesz T, Yeung P. Hyperbaric oxygen for idiopathic sudden sensorineural hearing loss and tinnitus. Cochrane Database of Systematic Reviews 2007, Issue 1. Art. No.: CD004739. DOI: 10.1002/14651858.CD004739.pub3.