The company Microtransponder have created a prototypal wireless neurostimulation device which it claims will potentially reverse the effects of chronic pain and tinnitus.

The device, which is reportedly smaller than a grain of rice, is implanted underneath the skin and delivers small electrical jolts to reprogram nerve impulses associated with pain and tinnitus. It is currently in the early stages of clinical research and has only been tested in rats [[i]].   

 The CEO of Microtransponder, Will Rosellini, recently testified as to the potential of the device in front of the US House of Representatives. You can see a video of this testimony at:

http://www.youtube.com/watch?v=u9FAi1CmGIc&feature=channel

Dexamethasone is a member of the glucocorticoid steroid family. A report by the Audiology Department at the University of Milan described encouraging results for the use of this drug as a therapeutic for tinnitus. 50 patients suffering with tinnitus were given dexamethasone administered intratympanically to the inner ear (injected through the ear drum), three times daily for three months. 34% of patients reported complete disappearance of tinnitus, and 40% reported a significant decrease in tinnitus intensity [[i]].

There are a number of other studies which support these positive findings.

There is evidence supporting the use of dexamethasone for tinnitus alleviation, but it has only been demonstrated as effective for tinnitus caused by inner ear disorders.

Zinc is an essential mineral required for the functioning of many cellular processes including maintenance of a healthy immune system, wound healing, cell division, growth, and smell and taste. In addition, zinc is heavily distributed in the auditory pathways of the brain and the cochlea in the ear, and is an essential component of the enzymes involved in the normal functioning of those areas.

A number of studies have reported that zinc has a beneficial effect on tinnitus, although these trials have been quite small[[i]].  

An interesting study in 2003 has found that tinnitus sufferers who had normal hearing had significantly lower zinc levels in the blood than normal healthy patients. This supports the idea that zinc deficiency may be involved in tinnitus generation [[ii]].

However, larger studies are needed to provide conclusive evidence whether zinc supplements are of significant and long-term therapeutic value to tinnitus sufferers.  Also be aware that elevation of zinc beyond the recommended daily allowance for an extended period can actually weaken your immune system and lead to side effects such as nausea, copper imbalance leading to anaemia, lethargy and disruption of co-ordination.

When using zinc it is best to take it separately from other minerals such as copper, iron, calcium as they can interfere with the absorption mechanism of zinc.

There are many types of hearing aids used to restore sound sensation to patients with hearing loss. Commonly, they are worn in the user’s ear or behind it with a conducting tube to deliver amplified external sound.

The restoration of hearing via hearing aids has also been discovered to alleviate tinnitus symptom. There is evidence that using hearing aids reduces awareness of tinnitus and improves the annoying masking of sounds and voices by internal tinnitus.

The mechanism of suppression is unclear but it has been suggested that restoring auditory input to the auditory nervous system, can reverse abnormal neuronal activity associated with tinnitus [[i]].

A study, using 25 years of data collected from patients attending a single tinnitus clinic, were conducted to investigate the role hearing aids can have in tinnitus modulation. A total of 1440 patients were given hearing aids, of which approximately 68% reported some improvement in tinnitus. Tinnitus suppression was not dependent on whether the hearing aid was fitted in one or both ears. In addition, digital hearing aids were discovered to be more effective in improving tinnitus perception when compared to older analogue types [[ii]].    

Other reports suggest that the best results are obtained when hearing aids are fitted to both ears, with the widest amplification setting and disabled noise controls [[iii]].

It has been suggested that the development of tinnitus may involve the release of chemicals that are toxic to the nervous system (neurotoxins). Therefore, it is believed that compounds which have neuroprotective and regenerative properties, may be able to reduce the severity of the condition [[i]].

Carovorine is a neuroprotective compound which has been shown to be effective in preventing damage to the cells in the inner ear when applied as an eardrop [[ii]].

However, these early studies have been conducted on animal models, so it remains to be seen whether caroverine is effective when tested on human subjects. Caroverine is currently not available in the USA.

Similar in concept to rTMR, electrical stimulation can induce changes in abnormal brain activity leading to a reduction in the perception of tinnitus. However, rather than using a magnetic field to alter neuronal activity, a weak electrical impulse is applied to the brain region of interest.

A large study comprising 248 tinnitus patients showed that 130 patients experienced a reduction in tinnitus severity, and 32 patients had complete relief, with electrical stimulation. However, a randomised placebo-controlled study in 2008 concluded that electrical stimulation was ineffective in reducing tinnitus severity [[i]].

A report by the Department of Neurosurgery in Antwerp, Belgium, has shown that electrical stimulation leads to a 97% reduction in patients who present with pure tone tinnitus when compared to 24% suppression for patients with a wider spectrum of tinnitus noise. A different study shows that intermittent ‘typewriter-type’ tinnitus was most responsive to treatment [[ii]].

There still needs to be a lot of research in this area. At present there appears to be no standard course for electrical stimulation therapy for tinnitus and there remains debate on which method of electrical stimulation is most effective [[iii]]. The dosing, methodology, and location of the treatment need to be explored, as well as the subgroup of tinnitus patients who will benefit most.

One advantage of this form of therapy over rTMS is that there is a lot more scope for self-treatment at home with a personal electrical device.  There are a few electrical stimulators emerging in the commercial tinnitus marketplace, a selection of which are described below.

Lidocaine is commonly used in dentistry as an anaesthetic. It has also been shown to ameliorate tinnitus when administered intravenously but its effects are generally short-lived at around 30 minutes to 1 hour. There are also a number of undesirable side-effects which limit its usefulness.

Emerging research over the past decade has revealed that tinnitus is associated with dysfunctional changes in neuronal activity in the brain, such as hyperexcitability in certain regions of the brain dedicated to sensing hearing. 

These new findings have led to experimental development on new therapies which aim to correct these unusual activities. Transcranial Magnetic Stimulation (TMS) is one of these new therapies.     

TMS was first demonstrated in 1985 and has been used to treat psychological conditions ranging from depression to schizophrenia. A coil of wire is placed above the skull in the affected region. Then a high magnetic field is produced which changes the activity of the neurones in the magnetic field.

Small repetitive doses of TMS (known as repetitive TMS or rTMS) lasting fractions of a second have been shown to induce long-lasting tinnitus reduction. Low frequency rTMS has been shown to reduce neuronal hyperexcitability resulting in tinnitus reduction.

Clinical Trials

A number of reports have shown that 1200 to 1500 short pulses of low frequency (1Hz) rTMS over a 5 day period can significantly reduce tinnitus intensity when compared to sham pulses. It is thought that the improvement in tinnitus is due to the reduction in neuronal hyperexcitability caused by low  frequency rTMS.  On average, 50% of patients in these scientific studies reported benefit. However, there are conflicting reports on the long lasting effects of the treatment. Studies have shown that the alleviation of tinnitus is observed for up to six months after therapy while other reports have observed no lasting effects [[i]].

rTMS has been proven by extensive research to be safe and well-tolerated. Around 10% of patients complain of mild brief headaches or physical discomfort on the skull, but no major adverse effects on the auditory system have been reported. In addition, It appears that rTMS induces greatest tinnitus reduction when applied in the acute stages of tinnitus.

Further research using larger sample sizes is needed to optimise the methodology and identify patient subgroups who will benefit best most from this treatment. rTMS does hold some promise for the future, and will benefit from the rising tide of new research in the neuroscience of tinnitus.

Klonopin or Clonazepam as it is otherwise known is a benzodiazepine in the same class as alprazolam and is used to treat panic disorders and seizures, amongst many other psychological conditions. In a substantial retrospective study on 25 years of clinical usage of Klonopin for the treatment of tinnitus, it was found that of 3,357 patients treated, 32% reported improvements in tinnitus. Patients were treated daily with either 0.5 or 1.0mg tablets of Klonopin.

The drug was most effective for vertigo patients where it completely or substantially controlled dizziness in 77% of patients. 16% reported adverse side-effects including: mild drowsiness, nightmares, depression, and lowering of libido [[i]]. 

There is also evidence that clonazepam is effective in the treatment of pulsatile tinnitus [[ii]].  There still remains the need for rigorous clinical trials into the effectiveness of the drug when compared with placebo. 

Carbamazepine is an anticonvusant used to prevent epileptic seizures, and it has also used been widely used to treat tinnitus.

Trials in animals with induced tinnitus, have shown that carbamazepine significantly suppresses the behavioral manifestations of tinnitus.  However, there have been few clinical trials supporting its efficacy in humans. As a result we are still unsure on the dosing for carbamazepine treatment, and on its long-term benefits for tinnitus alleviation.

Two Chinese studies in 2008 found that oral administration of carbamazepine had no beneficial effect on tinnitus when compared to a control group who did not receive the drug [[i]][[ii]].

Carbamazepine does carry serious side effects, and without clinical studies to support its efficacy, Its continued use for tinnitus is questionable.