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Zinc and Tinnitus (Research)

Research Summary


Arda, 2003    Human: randomized, prospective, placebo- controlled clinical trial   

Tinnitus of no obvious cause patients received 50 mg of zinc (or placebo) per day for 2 months.    82% of subjects receiving zinc therapy experienced improvement in their tinnitus (subjective improvement of at least 14%).Clinically favourable progress was observed in 46.4% of tinnitus patients treated with zinc (audiometry test of loudness of tinnitus).

Arda, 2003    Human: randomized, prospective, placebo- controlled clinical trial   

Blood zinc levels were measured in patients with tinnitus of no obvious cause.    31% of tinnitus patients of no obvious cause had below normal blood zinc levels.


Gersdorff, 1987    Human   

Tinnitus patients with low zinc levels were treated with supplemental zinc.    Positive results in tinnitus were observed in 52% of subjects - in 15% there was a good amelioration and in 37% there was a little but significant amelioration of their symptoms.  Males obtained better results than females.


Ochi, 1997    Human   

Serum zinc levels were measured in a group of tinnitus patients and in healthy controls.    Tinnitus patients had lower serum zinc levels compared with healthy controls.


Ochi, 1997    Human   

Tinnitus patients with low serum zinc levels received 34 – 68 mg of zinc per day for 2 weeks.    Zinc treatment reduce the severity of tinnitus in most patients with low serum zinc levels.


Ochi, 2003    Human   

Serum zinc levels were measured in tinnitus patients aged 20 – 59 and in matched healthy controls.    Patients with tinnitus who had normal hearing had significantly lower serum zinc levels compared to controls.Serum zinc levels were normal in tinnitus patients who also had hearing loss.


Shambaugh, 1985    Human   

Patients with both tinnitus and age-related hearing loss were treated with zinc for 6 months.  Serum zinc levels were measured.    Of those patients who had initially low serum levels of zinc, approximately 25% experienced an improvement in tinnitus after using supplemental zinc for 3 - 6 months.


Yetiser, 2002    Human   

Tinnitus patients were treated with zinc supplements (220 mg of zinc sulfate) for 2 months.    Zinc supplementation provided relief of tinnitus in some of the elderly subjects who had low dietary zinc intake.


Shambaugh, 1989    Review    None.   

Zinc deficiency may impair the function of the hearing nerve.  With zinc supplementation in patients who are marginally zinc deficient, there has been improvement in tinnitus in about 1/3 of elderly adults.


Coelho, 2007    Review    None.   

2% to 69% of tinnitus patients have zinc deficiency – elderly tinnitus patients more frequently have zinc deficiency.  Four of five studies indicated that zinc administration has a beneficial effect on tinnitus.



Peer-Reviewed Professional Journals

·    Arda, H. N., et al.  The role of zinc in the treatment of tinnitus.  Otol Neurotol.  24(1):86-89, 2003.

This study was designed to investigate the role of zinc administration in treatment of tinnitus.  This was a randomized, prospective, placebo-controlled study.  Patients with tinnitus were admitted to the ear, nose, and throat clinic of the authors' hospital.  Patients with tinnitus with no known pathologic conditions of the ear, nose, and throat; the mean age of 28 patients receiving zinc was 51.2 years, and that of 13 patients given placebo was 55 years.  Blood zinc levels were measured.  Frequency was detected by audiometry, and loudness of tinnitus was screened by tinnitus match test.  A questionnaire that scored tinnitus subjectively between 0 and 7 was given to patients before zinc treatment.  After 2 months of treatment (zinc 50 mg daily to zinc group, placebo pill containing starch to placebo group), all of the tests were performed again.  There was no difference in age, sex, duration of tinnitus, and affected ears between the patients treated with zinc and those treated with placebo.  Blood zinc levels were lower than normal in 31% of patients before treatment.  A decrease in tinnitus loudness by at least 10 dB was accepted as clinically favorable progress.  A decrease of more than 1 point in subjective tinnitus scoring was accepted as valid.  Clinically favorable progress was detected in 46.4% of patients given zinc.  Although this decrease was not statistically significant, the severity of subjective tinnitus decreased in 82% of the patients receiving zinc.  The mean of subjective tinnitus decreased from 5.25 +/- 1.08 to 2.82 +/- 1.81 ( < 0.001).  However, the decrease in severity of the tinnitus was not significant in patients receiving placebo.  It can be concluded that patients with tinnitus may have low blood zinc levels (31%) and clinical and subjective improvement can be achieved by oral zinc medication.  However, it remains to be seen whether the longer duration of treatment has more significant results.

·    Coelho, C. B., et al.  Zinc as a possible treatment for tinnitus.  Prog Brain Res.  166:279-2895, 2007.

Department of Otolaryngology, Head and Neck Surgery, The University of Iowa, Iowa City, IA, USA.

Zinc is an essential trace element present in all organs, tissues, fluids, and secretions of the body and it is widely distributed in the central nervous system, including the auditory pathway in synapses of the VIII nerve and in the cochlea.  Zinc is an essential component of Cu/Zn superoxide dismutase (SOD) and in certain enzymes and it is important for proper function of the immune system.  Three possible mechanisms have linked zinc to tinnitus; cochlear Cu/Zn SOD activity, synaptic transmission, and depression.  Evidences in the literature suggest prevalence rates of zinc deficiency in individuals with tinnitus from 2 to 69%, affecting elderly individuals more frequently.  Four among five small studies indicate that administration of zinc has a beneficial effect on tinnitus but these results still have to be confirmed in clinical trials with larger samples using a cross-over design, validated tinnitus handicap questionnaires, measurements of tinnitus magnitude, and accessing the coexistence of other symptoms such as depression, phonophobia, and hyperacusis.

·    Gersdorff, M., et al.  [The zinc sulfate overload test in patients suffering from tinnitus associated with low serum zinc. Preliminary report].  Acta Otorhinolaryngol Belg.  41(3):498-505, 1987.

The authors studied the efficiency of the zinc overloading in the treatment of patients suffering from tinnitus with hypozincemia.  The authors have positive results in about 52% of cases:  in 15% there was a good amelioration and in 37% there was a little but significant amelioration of their symptoms.  The authors have also found that this treatment of tinnitus with zinc of overloading is more efficient in males than in females.  It is also more efficient in types of tinnitus of a continuous character than in other types.

·    Ochi, K., et al.  [The serum zinc level in patients with tinnitus and the effect of zinc treatment].  Nippon Jibiinkoka Gakkai Kaiho.  100(9):915-919, 1997.

The authors measured the serum zinc level in patients with tinnitus and evaluated the effectiveness of zinc in the treatment of tinnitus.  Blood zinc levels were measured in 121 patients with tinnitus.  All patients were examined between 1995 and 1997 at the outpatient clinic of otorhinolaryngology St. Marianna University Toyoko Hospital.  47 patients who had received any drug such as a calcium channel blocker and others or had been affected by any diseases were excluded and therefore 74 patients consisting of 46 females (62%) and 28 males (38%) were investigated.  22 healthy volunteers served as a control group.  The mean age for the tinnitus group and the control group were 47.8 +/- 17.1 and 31.4 +/-8.2 years, respectively.  There was a significant decrease in serum zinc levels in patients with tinnitus compared with the control group.  Because there was a significant difference in age distribution between tinnitus and control groups, patients were selected by their age in order to neglect the effect of aging.  A significant difference was noted between the tinnitus group and control group.  Low blood zinc level was defined by using the mean and standard deviation for the control group.  The authors treated patients with low blood zinc levels.  A total dose of 34 - 68 mg of Zn++ was administered daily for over 2 weeks.  The degree of tinnitus was expressed on a numeric scale from 0 to 10 before and after treatment.  Blood zinc levels were significantly elevated after treatment.  There was a significant decrease in the numeric scale.  These findings suggest that zinc is useful in at least some patients suffering from tinnitus.  It is possible to classify patients with tinnitus by measuring serum zinc level and this leads to improvement of the overall treatment effect.

·    Ochi, K., et al.  Zinc deficiency and tinnitus.  Auris Nasus Larynx.  30(Supplement):25-28, 2003.

Department of Otolaryngology, St. Marianna University School of Medicine, Kawasaki, Japan

The objective of this study was to determine if there is a correlation between serum zinc levels and audiometric performance in tinnitus patients.  Seventy-three patients participated in this study.  Patient's age was restricted to 20-59 years.  All patients were examined at the otolaryngology outpatient clinic of the St. Marianna University Toyoko Hospital.  The control group consisted of 38 age- and sex-matched healthy volunteers.  A blood sample was taken to measure serum zinc levels. Hypozincemia was set at a level of the mean minus one S.D. in the control group.  An average hearing sensitivity was calculated as the mean value of hearing thresholds at five frequencies: 250, 500, 1000, 2000, and 4000 Hz.  Normal hearing was indicated when the hearing threshold at each of these frequencies was within 20 dB of normal thresholds.  There was no significant difference in serum zinc levels between patients with tinnitus and controls.  However, patients with tinnitus who had normal hearing had significantly lower serum zinc levels compared to controls.  In contrast, no significant difference in serum zinc levels was found between patients with tinnitus who had hearing loss, and controls.  A significant correlation between average hearing sensitivity and serum zinc level was observed.  These findings suggest that zinc is involved in the generation of tinnitus, especially in patients whose hearing is relatively normal.

·    Shambaugh, G. E.  Interviewed in:  Geriatrics.  38(4):21, 1983.

·    Shambaugh, G. E.  Zinc:  An essential trace element.  Clin Ecology.  2(4):203-206, 1984.

·    Shambaugh, G. E.  Zinc and presbycusis.  Am J Otol.  6(1):116-117, 1985.

Zinc was used to treat individuals who had both tinnitus and hearing loss (usually age-related).  Of those patients who had initially low serum levels of zinc, approximately 25% experienced an improvement in tinnitus after using supplemental zinc for three to six months.

·    Shambaugh, G. E.  Zinc for tinnitus, imbalance, and hearing loss in the elderly.  Am J Otol.  7(6):476-477, 1986.

[no abstract available].

·    Shambaugh, G. E.  Zinc: the neglected nutrient.  Am J Otol.  10(2):156-160, 1989.

Professor Robert Henkin first suggested that zinc deficiency might cause hearing-nerve impairment.  Assay of the soft tissues of the cochlea and vestibule revealed a zinc level higher than that of any other part of the body.  Previously, the eye was considered to have the highest level of zinc of any organ.  With zinc supplementation in patients who are marginally zinc deficient, there has been improvement in tinnitus and sensorineural hearing loss in about one-third of elderly adults.  The author believes zinc deficiency is one cause of presbycusis; by recognizing and correcting it, a progressive hearing loss can be arrested.

·    Yetiser, S., et al.  The role of zinc in management of tinnitus.  Auris Nasus Larynx.  29(4):329, 2002.

Department of ORL and HNS, Gulhane Medical School, Etlik, 06018, Ankara, Turkey

Several therapeutic modalities have been tried in patients with tinnitus. These trials have given rise to unsatisfactory results in most of the patients since the etiology and pathophysiology of tinnitus is unclear.  Significant correlation between tinnitus and decreased zinc level and also reduction in severity of tinnitus after zinc therapy has been reported in some clinical studies.  The aim of this study is to find out the prevalence of hypozincemia in patients suffering from tinnitus of various origins (presbyacusis, acoustic trauma and ototoxicity) at young and elderly population and to investigate the effect of zinc therapy upon the severity of tinnitus.  Forty consecutive patients with severe tinnitus were included in this study between April 1998 and May 2000.  There were 32 men (80%) and eight women (20%) with an age ranging between 19 and 67 (mean 40.6 years).  Eleven patients were over the age of 50. The zinc level was measured in non-diluted serum by flame atomic absorption spectrophotometry (normal values; 50-120 &mgr;g/dl) from fasting blood samples.  All the patients were given zinc pills 220 mg each, once a day and 2 h before lunch for 2 months.  The patients were required to fulfill a tinnitus scoring scale and a handicap questionnaire before and after treatment.  The Wilcoxon rank sum test and McNemar test were used for the statistical analysis.  Six patients were hypozincemic and seven patients had decreased serum zinc levels.  No significant change has been observed in frequency and severity of tinnitus measured by audiologic tests after zinc therapy.  Twenty-three (57.5%) of these patients reported some relief of tinnitus in the tinnitus scoring scale but the rate of improvement was ignorable (P>0.05).  Decrease in severity of tinnitus after zinc therapy in elder group was better than the younger ones.  This  study could not confirm the high incidence of hypozincemia in patients with tinnitus as reported previously.  Zinc therapy for 8 weeks presented no promising effect on tinnitus in three groups of patients and the difference between the rate of improvement in severity of tinnitus after zinc intake in patients with normal and low serum zinc level was not significant.  Zinc supplement provided relief of tinnitus in some of the elder people who apparently had dietary zinc deficiency.


Laypersons’ Publications

·    Callaghan, R.  Ringing in the ears.  Inside Good Health.  2:24-25, 1993.

Zinc is essential for proper ear function.  Many tinnitus patients have been found to have low levels of zinc.  Supplemental zinc alleviates (and sometimes totally cures) tinnitus in persons with low zinc levels).

·    Segala, M. (editor).  Disease Prevention and Treatment 3rd Edition.  Life Extension Media.  Florida, USA.  2000:675.

Some researchers have observed good results in tinnitus patients using 50 mg of zinc per day from zinc gluconate.