Allergies in Dogs Prevention | Controlling Common Dog Allergies

As noted in Allergies in Dogs Prevention, allergen avoidance provides the foundation that underpins most allergy preventative measures. Successful implementation of this principle may lead to a lessening of allergy frequency, severity and possible related infections e.g. secondary bacterial or fungi infections. Given that many dogs suffer from concurrent allergies (more than one type), a range of control measures may need to be applied in order to achieve the desired outcome.

Animal-related Allergies

If a dog has a known allergy to another animal, one should aim to avoid bringing the dog in contact with the creature, its waste products (excreta) as well as items derived from it e.g. hair, wool and lanolin, feathers or upholstery/milk/meat products etc.

Rodents and other vermin are ubiquitous and aside from the issue of disease, controlling their population locally is especially important should your dog be allergic to them. Unchecked, a single female mouse or rat can produce over 300 offspring in their lifetime. Therefore, one should inform your local authority or contact a local rodent control company at the first sign of a problem in or around your property.

Consider whether to avoid buying an allergy-prone dog breed. Furthermore, if you dog has been diagnosed with an allergy issue, consider not breeding with it to prevent such traits being passed on to subsequent generations.

Remember, not only can dogs have allergies to other pets such as cats, but it is possible for them to be allergic to other dogs and even people e.g. human dander.

Chemical and Material-related Allergies

There are literally 1000’s of potential chemicals and materials capable of triggering an allergic reaction in an individual hypersensitive to them. Skin symptoms and itchiness as well as airways and respiratory issues are most commonly associated with chemical and material-related allergies.

Identifying the specific allergen responsible for causing the symptoms can be problematic given the spectrum of potential allergens in this category. Moreover, commercial allergy tests will tend to limited in scope; if your dog happens to be sensitive to a less common allergen then diagnosis can be a lengthy and possibly expensive procedure. The problem can be compounded in the case of concurrent allergies (more than one allergy). A process of elimination through trial-and-error may help determine problematic allergens, although formal allergy diagnosis will often be a necessary requisite. When identified, allergen avoidance is the primary preventative measure.

Examples of common allergens in this category are dog/owners soaps, shampoos and conditioners (which can include products used by groomers that are labeled specifically for dog use), perfumes, fragrances and deodorizers, washing powders, detergents and other household cleaners,as well as metals, latex, fabrics, carpet fibers, pesticides and cigarette or wood burner/furnace smoke.

Food-related Allergies

Food allergies are thought to account for up to 20% of allergies affecting dogs and roughly 75% of these incidents are protein-related. Food allergies can be caused by plant or animal-derived ingredients.

An elimination diet (food trial/diet trial) employing provocative testing (provoking suspected condition) is currently the most effective method for diagnosing food allergies in dogs. The procedure will initially keep the dog on a strictly controlled diet of water and a hypoallergenic food source with limited, allergy friendly ingredients. However, the aim long-term is to provide a balanced and diverse diet whilst avoiding identified food allergens. Therefore, an elimination diet operates as both a diagnostic and ongoing preventative tool for food allergies.

Approximately 80% of dog food allergies relate to beef, diary and wheat allergens, whilst other common food allergens include celery, chicken, corn, dairy produce, eggs, fish and shellfish, lamb, legumes (e.g. peanuts and soybeans), tree nuts (e.g. almonds) and yeast. However, remember that almost any ingredient can trigger a response in a dog hypersensitive to it. Furthermore, no two individuals will have the same allergy profile regarding what they are sensitive to, the degree of sensitivity and the symptoms they experience.

In addition, keep in mind that a dog with a food allergy can be exposed to allergens either directly e.g. eating a product which contains an ingredient that it is allergic to, or indirectly e.g. you shake hands with someone who has touched/prepared an ingredient the dog is allergic to and then at a later time the dog licks your hand.

Insect-related Allergies

Various routes of allergen exposure can account for how a dog comes into contact with insect allergens e.g. skin contact, ingestion and inhalation. Allergens are present in the body parts and carcasses of insects as well in their excrement and fluid emissions, bites and stings.

Well known examples of this category include allergies to cockroaches, dust mites, fleas and bite/stings from ants, bees, spiders and wasps. Allergen avoidance can be achieved in various ways such as through eradicating the insect e.g. vermin control for cockroaches, good hygiene and regular cleaning of surface e.g. minimize dust mites, appropriate food storage facilities e.g. prevent storage mites, insect mesh on windows and doors e.g. block numerous flying insects from entering home, and the use of repellants e.g. ward off midges, mosquitos, bees and wasps.

Example: Flea Allergy

The following example of flea allergy control illustrates how achieving a successful outcome requires a holistic approach, given the dynamic interplay between the numerous variables involved i.e. understanding the underlying cause, obtaining an accurate diagnosis, undertaking appropriate treatment whilst aiming to minimize future outbreaks through various preventative measures. It highlights the importance of ongoing assessment and management of allergy conditions:

• Do you understand the nature of the ‘agent’ responsible for the allergy? For example, fleas do not fly but travel by jumping; they can survive for almost a week in temperatures as low as 1°C or 33.8°F etc.
• Do you have a grasp of the mechanism involved? i.e. life cycle of flea and mode of allergen transmission.
• Do you know the flea season? Typically, they are more problematic in the warmer months of year e.g. spring to early autumn in US or UK, although they can be an all-year-round pest, especially in warmer climates e.g. Florida.
• What allergy symptoms in dogs do fleas cause? Even a single flea/bite can be a significant problem for a dog allergic to them and the area affected is typically triangular-zoned i.e. middle back to rear legs and tip of tail. Aside from pruritus and other allergy symptoms, fleas can cause anemia and in extreme cases, they can be life-threatening for the young, old or those with compromised immune systems. In addition, fleas can transmit various diseases e.g. plague.
• How can you check for the presence of fleas? Comb the dog daily on light colored material for visual inspection of fleas, eggs, carcasses or flea feces. A simple test of whether the material contains flea feces involves adding a small quantity to a little water. If the particles release a blood red color then it is indicative of a positive result. Remember that the eggs and immature stages can be present in the dog’s bedding, around the house, in the furniture, on clothing etc.
• What can you do once a flea allergy is suspected or formally diagnosed by a veterinarian? Flea control includes the use of repellants and in severe cases, the use of medicated treatments e.g. Fipronil or Nitenpyram. Moreover, regular medicated baths help kill fleas and ease skin irritation.
• Think about the risk of cross contamination from other household pets, human carriers (including groomers and veterinarians) as well as various outside home risks e.g. fleas in the environment, various animal carriers such as feral cats and hedgehogs, the interiors of cars etc.

Medicine/Drug-related Allergies

Dogs can be hypersensitive to a multitude of possible ingredients found in medicines and drugs. This can include sensitivity to both the:

• Inactive/inert/excipient ingredients
  i.e. usually have no pharmacological effect
  e.g. additives, binding materials, dyes, preservatives and flavoring agents.
• Active ingredients (a.k.a. AI or Active Pharmaceutical Ingredient/API)
  i.e. responsible for the beneficial effects
  e.g. acetaminophen, cetirizine, cyclosporine etc.

Lysozyme and ovalbumin (associated with egg allergy), lactose (milk allergy) or soybean lecithin (soybean allergy) are examples of just a few of the many possible additives that can trigger a response in a hypersensitive subject.

Ironically, the active ingredient in medication used to treat allergy symptoms can itself sometimes trigger an allergy reaction. For example, some dogs are allergic to the anti-inflammatory topical corticosteroid, hydrocortisone, which is used to reduce allergy-related swelling, itching and pain. In addition, allergy-related secondary infections may be treated with antibiotics, yet these antimicrobial agents can trigger an allergic response in some dogs. In such cases, symptoms can range from various skin reactions, diarrhea or sudden vomiting through to more severe reactions such as seizures, anaphylaxis and possibly coma or death.

Being alert to the possibility of medicine-related allergies means that any problem can be dealt with sooner and more effectively. Given the potentially serious nature of this type of allergy, once a medicine-related allergy is suspected it is imperative to prevent future exposure to the problematic allergen. If in doubt, the owner should seek the advice of a veterinarian who will probably carry out various diagnostic tests to confirm the allergen source.

As with other categories, remember that medicinal allergies can result from contact (e.g. through topically applied drugs), ingestion (e.g. tablets) or via inhalation (e.g. sprays), as well as either directly (e.g. drug administered to dog) or indirectly (e.g. owner is being treated with a drug the dog is allergic to and lets the animal lick their hands) etc.

An interesting example of how allergen exposure can happen inadvertently has involved antibiotic-sensitive dogs suffering an allergic response following vaccinations to prevent viral conditions. Minute quantities of antibiotics added to the vaccine as a preservative (to prevent bacterial growth during production and storage) were believed to be the problem.

Microbial-related Allergies

Microorganisms can be associated with allergies in 2 ways, namely:

• Allergy symptoms and the related treatments can lead to the proliferation of problematic microbes. The microorganisms responsible for this type of problem are usually opportunistic pathogens. This means they normally co-exist with their host without causing a problem but only become detrimental when their normal environment changes. For example:

  Hot spots, caused by the canine skin resident bacteria Staphylococcus intermedius, occur following damage to the skin barrier e.g. through excessive scratching. This allows the normally benign microbes to invade and colonize the wound leading to an infection. As a result, pus-laden sores develop; blood poisoning becomes a life-threatening possibility should the bacteria enter the blood stream.

  Alternatively, a secondary yeast infection can develop following antibiotic treatment for a bacterial infection associated with certain allergy symptoms. A possible scenario could be that allergy associated inflammation of the upper respiratory tract results in a bacterial infection in this locale. Subsequent treatment of the bacterial infection using antibiotics disrupts the natural balance of microbes allowing a yeast infection to take hold. The resulting yeast infection may/may not develop in the locale of the original bacterial infection e.g. could develop in respiratory tract, urinary tract, vagina etc.

• Hypersensitivity to specific microbial antigens i.e. the bacteria or fungi itself and its related antigens triggers an allergy response.

By the nature of the problem, preventative measures for this category are more problematic than when compared, for example, with dealing with avoidance strategies for an allergy to pollen, nickel or beef. Therefore, whether the issue is controlling microbes associated with allergies or hypersensitivity to specific microbial antigens, a holistic approach aimed at boosting the dog’s immune system can be beneficial. Optimizing the immune system in this manner involves 2 components, namely:

Improving physical well-being:

• Having a nutritious and well-balanced diet.
• Regular exercise.
• A hygienic environment e.g. wash food bowls and bedding regularly, brush/groom/bathe as recommended for the breed, don’t let feces build-up in designated toilet area.

Improving emotional well-being:

• Loving environment.
• Lots of social interaction and playtime.
• Praising the animal.
• A sensible structured environment helps reduce animal stress. For example, dogs respond positively to being walked or fed at similar times of the day. In fact, most authoritative sources recommend feeding adult dogs once in the morning and once in the evening. The benefits are many, for example:
  • Helps establish a regular routine.
  • Gives the dog something to look forward to.
  • Helps build trust and a stronger family bond.
  • Changes in appetite are noteworthy because it usually correlates to physical well-being. Also, regular feed times tend to result in a dog going a toilet on schedule. Even well-trained dogs can become highly stressed when they need to defecate/urinate, so this helps minimize this problem.

Moreover, you will be much more likely to spot the early signs of sickness, disease and infections if you have invested time in building a close relationship with your dog. Both acute and chronic conditions can have deleterious impact on immune function. Therefore, if your dog appears unwell and doesn’t seem to be picking up after a few days, or should you be concerned, seek the advice of a veterinarian.

Finally, there has been considerable interest in recent years concerning the association between allergies, the immune system and intestinal bacteria. Studies have suggested that certain gut bacteria, in particular Clostridia, appear to confer allergy protection particularly against food allergies. Reducing the population of these microbes e.g. by using antibiotics, appears to increase the risk of allergies e.g. Bashir et al.2004, Tripathi et al.2012, Stefka et al. 2014.

Plant-related Allergies

Plants commonly associated with allergies include fungi (mold and mildew spores), grasses (e.g. blue, orchard, perennial rye, redtop, timothy), trees (e.g. aspen, cedar, cypress, elm, oak, willow) and weeds (e.g. cocklebur, ragweed, thistle). In addition, flowers/herbs such as amaranth, daises and ordinary sunflower, as well as shrubs/vines such as jasmine vine and wisteria can also be problematic.

Although ‘hay fever’ symptoms related to pollen are very common problem, plants can cause a variety of other issues:

• Plant material can trigger a food intolerance (non-immunological), food allergies (immunological) and are associated with potential allergic-cross-reactivity.
  The latter term refers to individuals (allergic to a specific allergen) who go on to develop an allergy to other foods containing the same allergen or allergens with a closely related physical structure. For example, individuals allergic to apples may also be sensitive to birch pollen or celery, cherry, peach and pear to name but a few. Similarly, an allergy to grass pollen can also be associated with a possible sensitivity to melon, oranges, tomato and watermelon.
• Various skin problems – either locally or at a distant body location – can develop when an individual comes into contact with plant material. For example, poison ivy, poison oak, and poison sumac contain in their leaves, stems and roots the potentially serious allergic triggering sap called urushiol. This can cause allergic contact dermatitis (Type 4 Hypersensitivity).
• Inhalation of various plant-related molecules can also trigger an allergic response. For example, hypersensitivity to fragrances, aromas from cooking or in the case of plants such as poison ivy, the smoke produced from burning plant material, can all lead to sensitivity of the tissues lining the airways and lungs.

Prevention, once again, centers on avoidance measure. Whether the problem is via inhalation e.g. (fungi spores or pollen), contact (e.g. poison ivy) or ingestion (e.g. chicken), it is imperative to identify the culprit through appropriate allergy diagnosis and then avoid exposure to the allergens.

Tips, Advice and General Considerations suggested numerous practical ways to help prevent allergies but of course, the route of allergen exposure will determine which approach is best. For example, in the case of inhalation, HEPA air filters and purifiers and regular wiping of surfaces might be most effective. Removing the offending plant/material from the home, work and play environments, and avoiding letting your dog run in wooded areas – where they can carry large volumes of allergens on their coat – could be helpful for contact allergies. In the case of ingestion/food allergy, adoption of an elimination diet (food trial) and using hypoallergenic dog food would probably be the best starting point.

However, given the variability in allergy symptoms, it is important to realize that flexibility is required when adopting preventative measures, and furthermore, a positive outcome will often require a holistic approach to the problem. Allergic-cross-reactivity (see above), highlights the complexity of tackling certain allergic conditions; in this case, an individual may still experience an allergy response despite avoiding foods/ingredient that they know they are hypersensitive to.

Other Allergies

As noted in Allergens, Antigens and Allergies, antigens are substances that the body considers to be foreign or dangerous and it responds by producing antibodies to them. However, not all antigens result in an allergic reaction and those that do are termed allergens.

Autoimmune disorders refer to when the immune system malfunctions and produces an immune response with antibodies (autoantibodies)/immune cells targeting its own healthy cells and tissues. The outcome is tissue damage and inflammation that can involve Type 2, Type 3 and Type 4 Hypersensitivity reactions. These responses differ from the classic allergy response associated with Type 1 Hypersensitivity, which is sometimes referred to as immediate hypersensitivity or atopic, anaphylactic or reaginic allergy.

There are over 80 autoimmune disorders e.g. celiac disease, rhuematoid arthritis, vasculitis and currently, the exact cause of these disorders is unknown. Although many disorders can be controlled with treatment e.g. corticosteroids, immunosuppressant or various disorder-specific drugs, there is currently no cure for autoimmune disorders.

With regards to prevention, the medical fraternities view is that there is no known prevention for most of these disorders. However, from anecdotal evidence, there are those who feel that measures aimed at reducing inflammation can be beneficial for autoimmune disorders. For example, eradicating hidden infections, eliminating possible food allergies and ruling out heavy metal toxicity may make a difference in some cases. Furthermore, tackling the causes of stress in dogs (e.g. chastising, isolation or irregular feeding) and regular exercise act as a natural anti-inflammatory. Additionally, certain nutrition and dietary supplements e.g. omega-3, vitamin C or probiotics, may help pacify the immune system.