Western botanicals for treating otitis media in animals

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Unlike conventional drugs, herbs and other botanicals make resistance nearly impossible for even the nastiest pathogens, and are effective weapons against the bacteria and fungi associated with otitis media in dogs, cats and horses.

Otitis refers to dermal or epidermal inflammation of the ear. Otitis externa or media are not diseases in themselves, but are symptoms of one or more preexisting conditions – and like dermatitis that occurs elsewhere on the body, the causes are rarely just skin deep. The primary difference between otitis and any other skin condition involves the unique environment in which inflammation and infection occur. The ear canal is like a fermentation vessel for pathogenic bacteria and fungi, especially if copious ear wax, dirt or other debris is present. This article looks at the herbs and other botanicals that can effectively treat otitis media in dogs, cats and horses.

Topical Interventions

Begin by cleaning the ears with a rinse solution that serves a dual purpose of removing dirt while inhibiting pathogenic bacteria and fungi residing in the ear canal. I prefer a base of cider vinegar, aloe vera juice and distilled water, to which a variety of essentials oils and herb extracts can be added. The overall solution should be fairly dilute, especially in the case of essential oils, which can otherwise be irritating to the point of aggravating rather than relieving inflammation. To prevent this and to assure optimal effectiveness of the formula, I recommend limiting essential oil components of any formula to ≤3% of total volume of the formula.

Most herb extracts (tinctures) can be used more liberally, depending of course on the choice of herbs. “Hot” herbs, such as garlic or peppermint, should not be used in concentrations exceeding 5%. Calendula on the other hand is quite forgiving, especially if used as a glycerite – my preferred form of any herb extract used in or on the ears. Glycerin lends its own healing benefits to a formula. Both antimicrobial and humectant, glycerin serves to absorb drainage and prevent pooling of exudate in dermal tissues.  

Botanicals for an ear rinse

All of the botanicals presented in this article are best used as components of the aforementioned ear rinse, twice a day. Here are some of my favorites, and how they work.

1. Cider Vinegar

Well known for its yeast-fighting antifungal and antibacterial actions,1 it’s an excellent cleanser that cuts through ear wax while inhibiting yeast and bacterial reproduction. Vinegar containing 5% acetic acid, in a concentration of ≤20% of the total formula, can be safely used with minimal risk of increased irritation.

2. Calendula Extract (Calendula officinalis)

The activities of Calendula extract have been compared to those of Fluconazole, a drug commonly used to combat blastomycosis, histoplasmosis and various other fungal infections.2,3 It is also antibacterial and serves as an excellent vulnerary agent, bringing soothing relief and accelerating cell reproduction and granuloma at the site of open sores, insect bites and other minor injuries.

3. Tea Tree Oil (Melaleuca alternafolia)

Tea tree oil is especially useful in the ears, and has strong activity against a broad variety of pathogenic fungi and bacteria.4,5 It can be safely used in concentrations of ≤3% on dogs, horses and most other animals; however, in my opinion, tea tree oil should not be applied consecutively for more than three days in cats, who tend to be hypersensitive to tea tree oil, especially when they lick it from their fur. Although I have yet to see any actual adverse events from the use of tea tree oil, a number of reports warn of acute hepatotoxicity, neurotoxicity and nephritic events when the oil is ingested in higher concentrations over non-specific periods of time. More is not better, and caution always rules – use this one sparingly on felines, and try to avoid direct ingestion of whatever formulation you use.

4. Lavender Oil (Lavendula off.)

This oil has been shown to be effective against at least 120 strains of pathogenic bacteria,6 and is among the safest essential oils for use in animals. It is also a remarkable healing agent and “carrier” for other botanical medicines; it serves as a quick-acting vasodilator that quickly increases blood circulation into the dermis. Lavender oil also lends a much welcomed calming effect, often to both the patient and practitioner!

5. Thyme Oil (Thymus off.)

Thyme oil is stronger and more reliable than lavender as a broad spectrum antimicrobial agent6 in solutions below 0.5%. This is due to its high concentrations of highly active thymol and carvacrol. As an example of how “less is sometimes better”, pick up a bottle of Listerine mouthwash and read the label. Thymol is a primary active ingredient – at a concentration of just 0.064%. Being an herbalist who believes that “the whole plant is greater than the sum of its parts”, I prefer to use thyme in the form of a whole leaf ethanol tincture. To use thyme in the ears, simply dilute 5ml of the 1:2 alcohol based oil into 250ml of a distilled water solution containing 20% cider vinegar. Rinse the ear liberally with the solution, twice daily.

6. Goldenseal (Hydrastis canadensis), Oregon Grape (Mahonia spp.) and Coptis Species

The roots of these plants are rich with berberine, a bright yellow, protoberberine-type isoquinoline alkaloid. Berberine offers a very broad spectrum of antibacterial, antifungal and antiviral activity. Several studies support this claim. In one, berberine was shown to be highly active against Fluconazole-resistant yeasts.7 It is also effective against a wide variety of pathogenic bacteria, including drug resistant staphylococcus aureus. Although most of these studies are in vitro, the usefulness of berberine stems from its ability to strongly inhibit, if not completely kill, pathogenic microbes on contact. This puts goldenseal and other berberine-bearing plants at the top of my list of resources for direct application. They also make a beautiful yellow dye – a feature that may be scorned by pet owners who don’t like temporarily stained fur, but welcomed by the herbalist who sees the staining as assurance that active principles of the plant remain present at the site of application.

7. Olive leaf (olea europaea)

Perhaps the “king” of antimicrobial herbs, olive leaf is simply amazing. Its healing powers have been known for a very long time. In the early to mid-1800s, olive leaf was found to be a very effective febrifuge remedy, and was seen as much more effective than quinine in the treatment of malaria. In 1962, Italian researchers recorded that oleuropein, one of several active components in olive leaf, could reduce blood pressure in both humans and animals. In 1969, the Upjohn Company, in recognition of a growing body of evidence illuminating not only the broad-spectrum antibacterial and antifungal properties of the plant, but also its remarkable activity against numerous protozoa and viruses, went to work to develop a new antiviral drug. As pharmaceutical research often goes, Upjohn focused on isolating a single component of olive leaf (oleuropein) in hopes of creating a new, patentable antimicrobial/antiviral super drug. They realized that olive simply does not work in the absence of a more complete representation of the plant’s chemistry. Hence, “the whole plant is greater the sum of its parts”. Like all herbs, the “entourage effect” of multiple chemical components, including (among others) coffee acid, verbascoside, luteolin 7-O-glucoside, rutin, apigenin 7-O-glucoside, luteolin 4’-O-glucoside, maslinic acid, hydroxutyrosol and oleocantha, all contribute to the wonders of this amazing botanical. Upjohn abandoned its pursuit, leaving behind a very impressive list of in-vitro activities. In fact, every germ that was inoculated in their studies was killed by olive leaf extract, including but not limited to multiple strains of Herpes virus, Candida yeast, and dozens of pathogenic bacteria. In a more recent invitro study, a scant 0.6% (v/v) dilution of olive leaf tea was shown to kill E coli within three hours. Candida albicans was completely killed by a 15% (v/v) extract.8 Olive leaf is effective in many forms (aqueous, ethanol or glycerin extracts) and is very safe. For applications against Otitis media, I recommend a 1:4 glycerite, diluted to concentrations between 10% to 20% in distilled water and up to 20% cider vinegar.

8. Rosemary Oil (Rosmarinus off. L.)

No article on Western botanical interventions against Otitis media would be complete without a strong mention of rosemary oil. There is good reason why this oil is used as a natural preservative in hundreds of natural foods and medicines. It can be applied safely and is very effective at inhibiting reproduction or killing (depending on concentration) an impressive variety of troublesome bacteria. In a 2003 study published in The Brazilian Journal of Biosciences, rosemary oil was found to be effective against 18 isolates of Staphylococcus pseudintermedius isolated from dogs.9 In another study, the oil was shown to be effective against six microbial species, including gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis), gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa), a yeast (Candida albicans), and a fungus (Aspergillus niger). Rosemary oil can be used with a broad margin of safety in dilutions of ≤3%. Like lavender, it may impart a calming effect upon an otherwise pain-tormented animal – or a nervous veterinarian. However, I find that stronger dilutions will sometimes result in an opposite, energizing effect.

Dietary Changes

Many cases of otitis media are influenced by food allergies, so any holistic approach will require a critical assessment of diet.

• Begin by removing all the “usual suspects” from the diet: wheat, soy, corn and their by-products.
• Meat by-products (leftovers from the human food slaughterhouse) and meat meal (parts of virtually any animal, from virtually anywhere but a human food process) should also be avoided in favor of whole, human-grade meats (e.g. turkey, fish, beef, chicken, lamb, duck, etc.).
• Artificial dyes or preservatives should also be eliminated. Instead, opt for foods that are preserved with natural vitamin E, rosemary oil, or other natural antioxidants.
• Supplementation should include immunotonics, such as Echinacea, to help boost the body’s fight against infection, and antimicrobials. Both can be used topically for direct intervention at surface tissues, and systemically to chase and inhibit pathogens from the inside out.

As many strains of pathogenic bacteria and fungi become increasingly resistant to our antibiotic arsenal, what may once have been a “simple case” of Otitis media can now become an all-out battle against infection. Fortunately, we have herbs to turn to. Unlike conventional antimicrobial drugs, herbs present complex chemistries that make adaptation and resistance nearly impossible for even the nastiest pathogens. Best of all, these herbs are easy to access and very safe to use.

1Aminifarshidmehr N. “The management of chronic suppurative otitis media with acid media solution”. Am J Otol. 1996;17:24–25.

2Preeti KC, Kulttan R. “Wound Healing activity of flower extract of Calendula officinalis”. J Basic Clin Physiol Pharmacol. 2009:20(1): 73-9. 

3Efstratiou E, Hussain AI, Nigam PS, Moore JE, Ayub MA, Rao JR. “Antimicrobial activity of Calendula officinalis petal extracts against fungi, as well as Gram-negative and Gram-positive clinical pathogens”. Complement Ther Clin Pract. 2012 Aug;18(3):173-6. doi: 10.1016/j.ctcp.2012.02.003. Epub 2012 Apr 25.

4Nenoff P, Haustein UF, Brandt W. “Antifungal activity of the essential oil of Melaleuca alternifolia against pathogenic fungi in vitro”. Skin Pharmacol 9 (6):388-394, 1996.

5Reichling J, Fitzi J, Hellmann K, Wegener T, Bucher S, Saller R. “Topical tea tree oil effective in canine localised pruritic dermatitis — a multi-centre randomised double-blind controlled clinical trial in the veterinary practice”. Dtsch Tierarztl Wochenschr. 2004;111(10):408–414.

6Sienkiewicz M, Lysakowska M, Ciećwierz J, Denys P, Kowalczyk E. “Antibacterial activity of thyme and lavender essential oils”. Med Chem. 2011 Nov;7(6):674-89.

7Anderson Ramos da Silva,  João Batista de Andrade Neto, Cecília Rocha da Silva, Rosana de Sousa Campos, Rose Anny Costa Silva, Daniel Domingues Freitas, Francisca Bruna Stefany Aires do Nascimento, Larissa Nara Dantas de Andrade, Letícia Serpa Sampaio, Thalles Barbosa Grangeiro, Hemerson Iury Ferreira Magalhães, Bruno Coêlho Cavalcanti, Manoel Odorico de Moraes, and Hélio Vitoriano Nobre Júnior. “Berberine Antifungal Activity in Fluconazole-Resistant Pathogenic Yeasts: Action Mechanism Evaluated by Flow Cytometry and Biofilm Growth Inhibition in Candida spp”. Antimicrob Agents Chemother. 2016 Jun; 60(6): 3551–3557.Published online 2016 May 23. Antimicrob Agents Chemother. 2016 Jun; 60(6): 3551–3557. 

8Markin D, Duek L, Berdicevsky I. “In vitro antimicrobial activity of olive leaves”. Mycoses. 2003 Apr;46(3-4):132-6.

9Catiana Oliveira Lima , Humberto Medeiros Barreto , Edeltrudes de Oliveira Lima , Evandro Leite de Souzaand José Pinto de Siqueira Júnior. “Antimicrobial effect of the essential oil from Rosmarinus officinalis L. against Staphylococcus pseudintermedius isolated from dogs”. Brazilian Journal of Biosciences. August 19, 2013.

Greg Tilford is CEO and formulator of Animal Essentials Inc., and an industry consultant and custom formulator for hundreds of veterinarians worldwide. He is the author of five books, including Herbs for Pets, the Natural Way to Enhance your Pet’s Life. Greg presents educational lectures, seminars and training to veterinarians, vet techs and office staff. He has taught courses at several veterinary medicine institutions and conferences, including the annual AHVMA conference. Greg serves as honorary advisor to the Japan Animal Wellness Association for international pet care professionals. He is a charter member of the Scientific Advisory Committee of the NASC. He founded the Animal Products Committee of the American Herbal Products Association and has served on Health Canada’s Expert Advisory Committee for Veterinary Natural Health Products.