Essential Oils for Tinnitus

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                                                         Essential Oils for Tinnitus

                                         (with detailed descriptions and references) 

                                                                   compiled by 

                                                          Robert M. DiSogra, AuD

An internet search for “essential oils for tinnitus” resulted in several commercial websites offering a variety of oils for tinnitus relief. None were able to support their claims with evidence based research.

PubMed from the National Library of Medicine (www.ncbi.nlm.nih.gov/pubmed) had no published articles in peer-reviewed journals suggesting that any essential oil can be effective specifically for tinnitus relief. 

The following is the combined list of the recommended essential oils "for tinnitus relief." They were cross referenced for any published research or documentation to support their indication for tinnitus relief.

NOTE: The US Food and Drug Administration has not approved any essential oil for tinnitus relief. This includes dietary supplements or nutraceuticals (see References #'s 1,2,3)

PRIMARY REFERENCES

I. Gruenwald, J, Brendler T, Jaenicke, C. PDR for Herbal Medicines 2007 Thomson Healthcare Inc., Montvale, NJ

Because it is still extremely hard to come by reliable information on the swarm of unregulated "dietary supplements" in today's market-place, this new edition continues to provide the reader with the closest available analog to FDA-approved labeling—the findings of the German Regulatory Authority's herbal watchdog agency, commonly called "Commission E." This agency has conducted an intensive assessment of the peer-reviewed literature on some 300 common botanicals, weighing the quality of the clinical evidence and identifying the uses for which the herb can reasonably be considered effective. 

PDR for Herbal Medicines is the product of one of the most thorough and inclusive examinations of the herbal literature ever undertaken. 

In the United States, herbal products are marketed under the provisions of the Dietary Supplement and Health Education Act of 1994, which prohibits their sale for the diagnosis, treatment, cure, or prevention of any disease. Enumeration of specific commercial preparations within an herbal monograph should not be construed as a claim or warranty of their efficacy for any purpose, by either the manufacturer or the publisher. Furthermore, it should be understood that, just as omission of a product does not signify rejection, inclusion of a product does not imply endorsement, and that the publisher is not advocating the use of any product or substance described herein. 

II. PubMed www.ncbi.nlm.nih.gov/pubmed

PubMed originates from the National Institutes of Health, US National Library of Medicine. PubMed comprises more than 29 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites. The Search feature will identify articles by keywords or author(s). The service is free to the public

DISCLAIMER

The information that appears in this list is for informational purposes only.

The use of an essential oil or combination of oils is at your own risk.

Skin irritation at the site could occur.

Dr. DiSogra and GoDaddy.com are not responsible of any injury or harm that could occur from using any of the essential oils for tinnitus from the list.

The reader is advised to consult an otolaryngologist (ear doctor) or audiologist* about your tinnitus. 

Use caution when using products that claim tinnitus relief from consumer testimonials rather than from information from evidence-based research.  

The following is the combined list of the recommended essential oils "for tinnitus relief." They were cross referenced for any published research or documentation to support their indication for tinnitus relief.” 

Some oils should be avoided by persons with a cardiac history, diabetics or by women who are pregnant or nursing. 

Name                                                Latin Name

1.   Basil Oil                                ocimum basilicum

2.   Cannabidiol (CBD Oil)        cannabidiol-dimethylheptyl

3.   Castor Oil                             ricinus communis

4.   Cypress Oil                          cupressus sempervirens

5.   Frankincense Oil                 boswellia carteri

6.   Garlic Oil                              allium sativum

7.   Ginseng Oil                          panax notoginseng

8.   Helichrysum Oil                  helichrysum immortelle; H. arenasrium)

9.   Lavender Oil                        lavandula officinalis, L. angustifolia 

10. Lilies Oil                                oleum lilia

11. Olive Oil                                olea europa

12. Onion Oil                              allium cepa

13. Patchouli Oil                        pogostemon cablin 

14. Petitgrain Oil                       citrus aurantium

15. Rehmannia Oil                    rehmannia glutinosa 

16. Saline Solution                    sodium choloride and water

17. Spotted Orchis Oil              orchis masculata 

NOTE: Numbers in the parentheses ( )  refer to the source of the information - see REFERENCES  

Basil Oil (ocimum basilicum) (also known as green basil, holy basil)

Basil oil is an antispasmodic, meaning it can act upon the smooth muscle cells in the ears and calm down a throbbing and pulsating sensation.(4)

Oil of basil is the essential oil extracted from the dried aerial parts of ocimum basilicum by steam distillation. It contains estragole (chavicol methyl ether), lina-lool and eugenol. The oil demonstrates an antimicrobial effect.(5) 

Unproven Uses: Among traditional uses for the oil are wounds, rheumatic complaints, colds and chills,

contusions, joint pains and depression. [Author’s note: tinnitus not included.]

Precautions (5)

Pregnancy: The herb contains about 0.5% essential oil with up to 85% estragole. Because of the high estragole content in the essential oil, the herb should not be taken during pregnancy. 

Estragole is suspected to be carcinogenic and genotoxic, as is indicated by a report of the European Union, Committee on Herbal Medicinal Products.(6)

Because a mutagenic effect in vitro and a carcinogenic effect in animal experiments have been demonstrated for estragole, oil of basil should not be administered during pregnancy or while nursing. 

Basil oil should not be given to infants or small children. 

NOTE: PubMed had 66 basil oil related articles (as of 11/25/18) in their database. Adding the word ‘tinnitus’ to the search word yielded no published articles in peer-reviewed journals suggesting that basil oil can be effective for tinnitus relief.

Cannabidiol Oil (CBD Oil) (cannabidiol-dimethylheptyl)

CBD is a naturally occurring cannabinoid constituent of cannabis. It is the non-intoxicating marijuana extact. 

CBD is being produced without any regulation, resulting in products that vary widely in quality.(7)

CBD is FDA approved for childhood epilepsy – however, it may interfere with anti-epileptic drugs (adults and children).(8)

Smith and Zheng(9) noted that there is a hypothesis that tinnitus is a form of sensory epilepsy, arising partly from neuronal hyperactivity in auditory regions of the brain such as the cochlear nucleus and inferior colliculus…anti-epileptic drugs [oral] are used in some cases as a potential treatment option.

According to the website “How to Cure”10 CBD oil…is an anticonvulsant and has antiepileptic effects which make it quite useful in relaxing the hyperactivity of neurons and soothing the noise.(11) [Author’s note: although this published article is cited, there is no reference to tinnitus in the article].

NOTE: There is one Herbal Monographs(5) on this plant from Commission. Tinnitus is not listed under Indications and Usage 

NOTE: PubMed had no published articles in peer-reviewed journals suggesting that this CBD oil can be effective for tinnitus relief. 

Castor Oil (ricinus communis)

Home Remedies for Life's website(12) states that castor oil...

• contains antibacterial, anti-viral and anti-inflammatory properties.
• helps in restoring the cell function inside the ears.
• strengthens  the system to protect it against the fungi and bacteria that collect in the ear.
• helps to  clean the ear channels.
• is known to  treat various ear problems like cochlea which may be one of the problems  for tinnitus

NOTE: There are no references listed to support these statements.

Castor oil can be the best remedy for your ear. Its antibacterial, anti-inflammatory, and anti-viral properties prevent bacteria and fungi from collecting in the ear.(13) [Author’s note: although this published article is cited, there is no reference to tinnitus in the article.] 

It also keeps the ear channels clean and restores the function of ear cells.(10) 

NOTE: PubMed had 2423 castor oil related articles (as of 11/25/18) in their database. Adding the word ‘tinnitus’ to the search word yielded no published articles in peer-reviewed journals suggesting that this essential oil can be effective for tinnitus relief. 

NOTE: There is one Herbal Monographs on this plant from Commission E.(5) Tinnitus is not listed under Indications and Usage (Chinese, Indian and Homeopathic medicine). It is primarily used as a laxative.

NOTE: PDR for Herbal Medicines(5) advises that castor oil not be used during pregnancy and while nursing; not intended for children under 12 years of age.

Cypress Oil (cypressus sempervirens)

Cypress acts as an expectorant for coughs, head colds and bronchitis.(5) It is able to stimulate blood circulation while also helping calm the nervous system. Pulsing tinnitus, the result of a problem in blood circulation, benefits greatly from cypress oil.(4)

NOTE: Less than 10% of tinnitus patients suffer from pulsatile tinnitus.(14)

Cypress essential oil is used to stimulate blood circulation. If a person has pulsing tinnitus, they may have a problem with the blood circulation in their ears. Using cypress oil around the ear will increase the blood circulation and lessen the intensity of the ear’s ringing.(15)

NOTE: there is one Herbal Monographs on this plant from Commission E.(5) Tinnitus is not listed under Indications and Usage.

NOTE: PubMed had no published articles in peer-reviewed journals suggesting that this essential oil can be effective for tinnitus relief. 

Frankincense Oil (boswellia carteri)

Old French: franc encens or “high quality incense”…known to exist in the middle east for thousands of years. Oil is produced by steam distillation of the tree resin…balsamic-spicy, slightly lemon fragrance

Indications and usage: [frankincense] is considered obsolete for medicinal use because its mode of action has not been documented. In vitro, the alpha and beta boswellic acids showed antimicrobial activity and inhibited the complementary system. The mucin, triterpene and essential oil content make application for respiratory conditions and its use for wounds seem plausible.(5)

NOTE: there is one Herbal Monographs on this plant from Commission E.(5) Tinnitus is not listed under Indications and Usage. The drug is considered obsolete.

NOTE: PubMed had no published articles in peer-reviewed journals suggesting that frankincense can be effective for tinnitus relief. 

Garlic Oil (allium sativum)

The compounds in garlic incluse alliins (alkylcysteine sulfoxides): in particular allylalliin, propenyl alliin and methylalliin (including their gamma-glutamyl conjugates. The alliin in the drug is antimicrobial, lipid-reducing, anti-oxidative and fibrinolytic.(5)

Frequent contact with the drug may result in allergic reactions such as contact dermatitis.(16)

It is unproven for tinnitus in Indian medicine and homeopathy. Garlic us not to be used while nursing. Concomitant use of garlic with anticoagulants such as Coumadin and antiplatelets such as aspirin and dipyridamole could increase the risk of bleeding due to the effect of garlic on platelet aggregation and fibrinogen.(5)

NOTE: There is one Herbal Monograph on this plant from Commission E.(5) Tinnitus is not listed as an approved indication or usage.

NOTE: there is one Herbal Monographs on garlic from Commission E.(5) Tinnitus is not listed under Indications and Usage. The drug is considered obsolete.

Ginseng Oil (panax notoginseng)

“The pharmacological effects of FBP [D-Fructose-1,6-bisphosphate] include antihypertensive, anticancer, hepatoprotective, and cardiovascular protective effects. The compounds in FBP include saponins, flavonoids, volatile oils, and polysaccharides. The total saponins are the principal bioactive components. In modern applications, FBP is used to treat hypertension and tinnitus.” (17)

Maternal use of ginseng has been associated with neonatal androgenization, thus it is not recommended for use during pregnancy or lactation.(18)

NOTE: There is one Herbal Monograph on this plant from Commission E. Tinnitus is not listed as an approved indication or usage. However, caution should be taken when taking an antidiabetic agent or insulin to lower blood glucose because ginseng has been shown to have hypoglycemic effects…Caution should also be taken in patients with cardiovascular disease. Due to the antiplatelet effect of ginseng, avoid concomitant use with antiplatelet agents or NSAIDS.(5)

NOTE: PubMed did not identify any published research in their database to support claims that ginseng can be used specifically for tinnitus relief.

Helichrysum Oil (also known as Helichrysum immortelle, Helichrysum arenasrium)

The drug has antibacterial principles, and is mildly choleretic and mildly spasmolytic. 

Compounds: Flavonoids: in particular isosalipurposide (intensive yellow chalcone glycoside), naringenin-5-glucosyl-gIucoside, helichrysin A and B (C-2-enantiomeric narigenin-5-O-glucosides, B-salipurposide). Phthalides: including 5-methoxy-7-hydroxy-phthaIides and their monoglucoside. Alpha-pyrone derivatives:arenole, homoarenole. Sesquiterpene: bitter principles. Volatile oil: traces; Caffeic acid derivatives.(5)

The Home Remedies for All website states that “this is one of the most powerful oil widely used in tinnitus [no supportive documentation with this statement]. Its capabilities to repair blood vessels and nerves and to reduce inflammation are the main reasons for it to be very effective in tinnitus symptom relief.(19)

 “Has anti-inflammatory properties and is generally soothing to the nerves.(20)

Helichrysum essential oil is known to provide relief from tinnitus. It attributes to the healing and anti-inflammatory properties of the oil.(21) The primary cause behind tinnitus is inflammation in the ear or problem in the nerves of ears and the neck. Using helichrysum oil can be of great help as it reduces the swelling.

 Helichrysum oil is also known to drain excess fluids from the body. Thus, it effectively prevents the buildup of earwax. To increase the effect, combine Patchouli oil with Helichrysum oil.(10)

NOTE 1: There was one Herbal Monographs on this plant from Commission E.(5) Tinnitus is not listed as an approved usage.

NOTE: PubMed had 266 helichrysum oil related articles (as of 11/15/18) in their database (including the Sala article(21) referenced above). Adding the word ‘tinnitus’ to the search word yielded no published articles in peer-reviewed journals suggesting that helichrysum oil can be effective for tinnitus relief.

Juniper Oil (juniperus communis)

Volatile oil (1-2%); make-up is very dependent upon the source of the drug, chief components monoterpene hydrocarbons, for example alpha-pinene, beta-myrcene, gamma-muurolen, sabinene, additionally including among others limonene, beta-elemene, beta-caryophyllene, beta-pinene, gamma-cadinene, terpinene-4-ol.(5) 

The diuretic effect is attributed to the essential oil content. The drug works to lower blood pressure and as an antidiabetic. Not to be used during pregnancy.(5)

A great detoxifier, juniper cleanses the blood. This essential oil releases toxins from the body and promotes the excretion of uric acid crystals. This detoxifying action of juniper is particularly useful in treating tinnitus.(4)

NOTE: There was one Herbal Monographs on this plant from Commission E (5) Tinnitus is not listed as an approved usage.

NOTE: PubMed did not identify any published research in their database to support claims that juniper oil can be used specifically for tinnitus relief.

Lavender Oil (lavandula officinalis, Lavandula angustifolia)

This is the oil of the lavender herb (organic lavender essential oil). 

A popular essential oil because of its relaxing and sedative properties as well as its distinct sweet floral scent. Lavender oil can help calm and soothe the mind and body. This can eliminate stress, anxiety, fear, and tension, all of which contribute to increased tinnitus intensity.(4)

Caution: Lavender might decrease blood pressure in some people. Taking lavender along with medications used for lowering high blood pressure might cause blood pressure to go too low. Do not take too much lavender if you are taking medications for high blood pressure.(5)

NOTE : There is one Herbal Monographs on this plant from Commission E(5) Lavender is not indicated for tinnitus relief.

NOTE: PubMed had one article reporting on the anti-inflammatory effects of lavender on the central nervous system(22) but no other published research in their database to support claims that lavender oil can be used specifically for tinnitus relief.

Lilies Oil (oleum lilia)

This is an anti-inflammatory oil indicated for earaches, tinnitus, headache, kidney pain, bladder pain and uterine discomfort.(23)

NOTE: There are no Herbal Monographs on this plant from Commission E.(5)

NOTE: PubMed had no published articles in peer-reviewed journals suggesting that this lilies oil can be effective for tinnitus relief.

Olive Oil (olea europa)

Compounds: Chief fatty acids: oleic acid (56-83%), palmitic acid (8-20%), linoleic acid (4-20%), Steroids (0.125 to 0.25%): beta-sitosterol, delta7-stigmasterol, delta5-avenasterol, campesterol, stigmasterol, Tocopherols (0.02%). (5)

Olive oil can be an excellent remedy to treat tinnitus. It is rich in antioxidants and fatty acids that are a solution for all our ear troubles. Further consuming the oil can calm inflammation and treat tinnitus.(10)

NOTE: PubMed did not identify any published research in their database to support claims that olive oil can be used specifically for tinnitus relief.

NOTE: There was one Herbal Monographs for olive oil from Commission E.(5) Tinnitus was not listed as an approved use.

Onion Oil (allium cepa)

Compounds: Alliins (alkylcysteine sulphoxides): in particular allylalliin (allyl-L (+)-cysteine sulphoxide) and its gamma-glutamyl conjugates, that in the course of cutting up either the freshly harvested bulbs or those that have been already dried and then re-moistened, are transformed into the so-called alliaceous oils; Fructosans (polysaccharides, 10-40%); Saccharose and other sugars; Flavonoids: including quercetin-4'-O-beta-D-glucoside (spiraeoside); and Steroid Saponins.(5)

Not indicated for tinnitus relief (Indian medicine, Chinese medicine and homeopatghy).(5)

Has antibacterial properties [not listed in the PDR for Herbal Medicine(5) 

WOW Remedies states that just 3 drops in the ear will “…help alleviate your tinnitus symptoms”(20)

NOTE: There was one Herbal Monographs for olive oil from Commission E.(5) Tinnitus was not listed as an approved use.

NOTE: PubMed did not identify any published research in their database to support claims that onion oil can be used specifically for tinnitus relief.

Patchouli Oil (pogostemon cablin) 

Patchouli essential oil comes from a species of plant from labiatae family that include lavender, mint and sage. 

It’s chemical composition include Volatile oil (1.5-4%):chief components are sesquiterpenes, including among others patchouli alcohol (35%), alpha-guaiene (20%), alpha-bulnesen (20%), beta-patchoulen (2%) as well as nordehydropatchoulol (aroma-bearer); Sesquiter-pene pyridine alkaloids were isolated from the volatile oil, including among others patchouli pyridine, epiguai pyridine.(5)

There is no known medicinal use. The herb is used in perfumes and cosmetics.(5)

NOTE: PubMed did not identify any published research in their database to support claims that this plant can be used specifically for tinnitus relief.

Petitgrain Oil (citrus aurantium)

In perfumery and aromatherapy it adds a fresh scent.

“…it promotes muscle contraction in and around the ears to give tinnitus relief. Made from leaves of bitter orange tree this aromatic essential oil acts as a sedative, relaxant, tranquilizer and cardiac tonic helping in both emotional and physical ways.(10)

It can act as an antispasmodic, help to relieve tinnitus due to muscle contraction. Petitgrain is also known for its strong calming and sedating properties.(4)

NOTE: There were no Herbal Monographs for petitgrain from Commission E.(5)

NOTE: PubMed did not identify any published research in their database to support claims that petitgrain can be used specifically for tinnitus relief.

Rehmannia Oil (also known as Di-Huang) (rehmannia glutinosa)

Compounds: Iridoids: chief component catalpol (0.3 to 0.5%), including ajugol, aucubin, melittoside, rehmaniosides A to D; Monoterpene: rehmapicroside; Ionone glucosides: rehmaionones A and B; Monosaccharides/oligosaccharides: stachyose (10%, based upon the fresh weight), saccharose, raffinose, D-fructose, D-glucose, D-galactose; Steroids: sterols, including beta-sitosterol, campesterol, stigmasterol.(5)

The phenolic glycosides of the drug are antibacterial, immunosuppressive and antihepatotoxic in effect.the root tuber is either cleaned and used as it is (called Shoudihuang or Xiandihuang) or is moistened with steam, cut into slices and dried over a fire until the water is reduced by 80% (Shengdihuang). Shoudihuang (fresh root tuber) is used for “…vertigo, tinnitus, impaired hearing,-hyperhidrosis, diabetes and increased frequency of urination. …”(5)

NOTE: There is one Herbal Monograph on this plant from Commission E.(5)  Tinnitus is not listed as an approved indication or usage but listed as a use in Chinese Medicine (see above).

NOTE : PubMed did not identify any published research in their database to support claims that this plant can be used specifically for tinnitus relief.

Saline Solution (sodium chloride and water)

DIY Health Remedies states that “If tinnitus is the result of nasal congestion or blocked sinuses use a saline solution: 1 tsp glycerine + salt + warm water: spray into each nostril. The results will “cure tinnitus effectively.”(24)

NOTE: PubMed did not identify any published research in their database to support claims that a saline solution can be used specifically for tinnitus relief.

Spotted Orchis Oil (orchis maculata)

This is the spotted orchid. The specific Latin name "maculata" (= spotted) refers to the stained leaves. 

This oil is an analgesic. It is used for tinnitus and hearing loss, headaches, eye disease, skin irritation, corns, herpes, cystitis, gastroenteritis.(25)

NOTE: There were no Herbal Monographs on this plant from Commission E.(5)

NOTE: PubMed had no published articles in peer-reviewed journals suggesting that this plant oil can be effective for tinnitus relief.

1. DiSogra, RM. Over the counter tinnitus relief products. ESCO/Oaktree Products Publ. 2015

2. DiSogra, RM. Over-the-counter dietary supplements for tinnitus: do they really help? Tinnitus Today, Vol. 39, No. 3 December. pp.16-18, 2014

3. DiSogra, RM. OTC tinnitus relief products: why reading the label is important. Audiol Today July/August 2014

4. Garikiparithi M. 7 essential oils for tinnitus: benefits and how they can treat ringing ears. June, 2017 Hear Health

5. Gruenwald, J, Brendler T, Jaenicke, C. PDR for Herbal Medicines 2007 Thomson Healthcare Inc., Montvale, NJ

6. Committee on Herbal Medicinal Products. Final public statement on the use of herbal medicinal products containing estragole.

http://www.ema.europa.eu/docs/en_GB/document_library/Scientific_guideline/2010/04/WC500089960.pdf

7. WebMD. www.webMD. 5/5/18 

www.webmd.com/pain-management/news/20180507/cbd-oil-all-the-rage-but-is-it-safe effective#1

8. US Food and Drug Administration. www.fda,gov. Retrieved 25 June 2018

9. Smith PF, Zheng Y. Cannabinoids, cannabinoid receptors and tinnitus. Hear Res. 2016 Feb;332:210-216

10. How to Cure: https://howtocure.com/essential-oils-for-tinnitus/

11. Carlini EA, Cunha JM. Hypnotic and antiepileptic effects of cannabidiol. J Clin Pharmacol. 1981 Aug-Sep;21(S1):417S-427S

12. Home Remedies for Life. www.homeremediesforlife.com

13. Iqbal J, Zaib S, Farooq U, Khan A, Irum BibI I, Suleman S. Antioxidant, antimicrobial, and free radical scavenging potential of aerial parts of periploca aphylla and ricinus communis. ISRN Pharmacol. 2012; 2012: 563267

14. Kircher ML, Standring RT, Leonetti JP. Neuroradiologic assessment of pulsatile tinnitus. Otolaryngol Head Neck Surg. 2008;139(Suppl)

15. Health Watch List. www.healthwatchlist.com/essential-oils-ringing-ears 

16. Asero R, Mistrello G, Roncarolo D et al., A case of garlic allergy. J Allergy Clin Immunol 1998 Mar;101(3):427-8

17. Zhang S, Chen C, Lu W, Wei L. Phytochemistry, pharmacology, and clinical use of panax notoginseng flowers buds. Phytother Res. 2018 Nov;32(11):2155-2163

18. Awang, DV, Maternal use of ginseng and neonatal androgenization. J Amer Med Assn. 1991 Jul 17;266(3):363

19. Home Remedies for All. www.homeremediesforall.com

20. WOW Remedies. www.wowwremedies.com

21. Sala A, Recio M, Giner RM, Máñez S, Tournier H, Schinella G, Ríos JL. Anti-inflammatory and antioxidant properties of Helichrysum italicum. J Pharm Pharmacol. 2002 Mar;54(3):365-371 [NOTE: this study used mice]

22. Koulivand PH, Khaleghi Ghadiri M, Gorji A. Lavender and the nervous system. Evid Based Complement Alternat Med. 2013

23. Mahdizadeh S, Khaleghi Ghadiri M, and Ali Gorji A. Avicenna's canon of medicine: a review of analgesics and anti-inflammatory substances. Avicenna J Phytomed. 2015 May-Jun; 5(3): 182–202

24.DYI Health Remedy: www.diyhealthremedy.com/home-remedies-for-tinnitus/

25. Mahdizadeh S, Khaleghi Ghadiri M, and Ali Gorji A. Avicenna's canon of medicine: a review of analgesics and anti-inflammatory substances. Avicenna J Phytomed. 2015 May-Jun; 5(3): 182–202

There are no essential oils approved by the US Food and Drug Administration (FDA) for tinnitus relief.

Tinnitus is a SYMPTOM of a medical problem which should be evaluated by an otolaryngologist (ENT physician) and an audiologist to determine the CAUSE. 

After a diagnosis is made a treatment plan will be initiated and monitored professionally. 

Consumer testimonials are no substitute for proper medical/audiological care.