dealing with allergies
TYPES OF ALLERGIES
Flea Allergy Dermatitis (FAD), a common cause of dog allergies, is a negative reaction to flea bites, whether one or several. When bitten, flea saliva enters the bite wound, inserting multiple histamine-type components that ignite hypersensitivity. This reaction spawns Pruritis and papulocrustous lesions (crusty lesions) of the skin. The itch instigates excessive scratching that in turn leads to additional dermatological complications (e.g. infection) which most often require antibiotics.
Food allergies are an adverse response to a particular ingredient in the food, generally the protein source. Examples include egg, beef, chicken, pork, or occasionally a carbohydrate such as corn, wheat, or soy. Typically the allergy develops from the dog eating the food over time vs. responding to a change in diet.
While any dog can develop food allergies, some breeds are genetically prone to the condition, such as Golden Retrievers, Cocker and Springer Spaniels, and West Highland White Terriers.
Atopic Dermatitis (environmental allergies) is an inherited, chronic skin disease that affects many dogs, despite age, breed or mix, although it is quite common in Terriers. Continuous itching, scratching and a reoccurring rash proliferate as a result of environmental elements, including dust, pollen, and mold spores. A more daunting ailment, there is no cure, but developments in medicine have helped to control the condition thanks to the production of advanced allergy meds for dogs.
Flea allergy symptoms are often noticeable on the lower back and beginning of tail while gradually migrating across the entire body. Skin typically presents signs of Pruritis, browned hair from licking, alopecia, papulocrustous lesions, excoriation, erythema, moist dermatitis (hot spots), and the presence of fleas and/or flea feces. If not treated promptly, the problem is compounded by a secondary bacterial or yeast infection. Affected dogs are found to scratch and chew excessively at the flea bites and often have tapeworms and tapeworm excrement on the anus as a result of digesting fleas while chewing. Since flea season peaks in the late summer, FAD (flea-allergic dermatitis) often remains true to seasonal flares.
Food allergy patients, however, find themselves affected throughout the year with little or no relief. Symptoms include ear infections, scratching and/or licking with noticeably dark stains on feet or limbs, as well as hair loss specific to the back, tail and stomach.
Atopic Dermatitis demonstrates itself predominantly by signs of excessive itching and scratching, noticeably on the face and feet. Other areas of the body can additionally exhibit signs of inflammation, moisture, and damaged skin from the scratching and chewing. Hair loss, lesions, and secondary infections may also be present upon examination.
Flea allergies can only be controlled by eliminating fleas and preventing flea infestation not only on the dog, but in the home, as well. Unfortunately, while secondary infections are able to be treated with antibiotics, there are no designated allergy meds for dogs suffering from FAD. As a result, proper use and consistent application of flea preventative, as well as destroying flea life and habitats in the home, is the only way to provide flea allergy relief for dogs.
The cause of infestations and hypersensitivity outside of spring and summer months often confuse dog owners. To the surprise of many, a high flea count in cold weather results not from outdoor fleas, but instead from fleas of various life stages and eggs harboring within furniture and carpets. When the heat is turned on during colder weather, the warmth encourages eggs to hatch. As larva mature, they feed and multiply daily by the hundreds. As a result, within the fall and winter seasons, fleas remain active and continue to feed on both pets and humans.
Elimination in the home includes thoroughly vacuuming, as well as washing dog clothes, beds, toys and blankets in hot water. To destroy all life cycles of the flea, appropriate products must be used and directions strictly followed for three complete treatments at two week intervals (Shrum, DVM, Interview, April 2015).
Food hypersensitivities, like flea allergies, do not respond to specific allergy meds for dogs. Allergy relief for dogs sensitive to proteins or carbohydrates relies on the task of elimination. Diagnosis is determined by removing the current food and adhering to a diet containing proteins/carbohydrates to which the dog was not previously exposed and has therefore never eaten. For a 10 to 16 week duration, it is vital that the dog not receive any other type of food or treats alongside the new diet. If the symptoms resolve during this time frame, yet revisiting the previous diet prompts a reoccurrence of symptoms, the dog must return to and remain on the new protein.
Atopic Dermatitis is addressed differently than other dog allergies. Diagnosis greatly depends on elimination of other causes of Pruritis such as bacteria, yeast, and flea or food allergies. Once these instigators are ruled out, dermatological tests determine the cause of the hypersensitivity.
The two types of tests for pets, intradermal allergy testing (testing the skin) and serologic allergy testing (testing serum samples), help determine the cause of the allergy. Once defined, proper treatment can be administered.
As a guideline for allergy relief for dogs, Thierry Olivry, DrVet, PhD, DipECVD, DipACVD recommends that treatment for Atopic Dermatitis include elimination of “flare factors.” This consists of encouraging owners to bathe dogs with non-irritating shampoo, properly administer flea and tick preventative, and control dust mites. It is also proposed that attending veterinarians provide specific antimicrobial therapy when necessary, use intermittent application of topical glucocorticoids for focused areas (e.g. the foot), and treat with oral glucocorticoids or ciclosporins, as well as subcutaneous interferons.
LIVING WITH ALLERGIES
Unfortunately, dog allergies cannot be cured, and treatment is necessary for the life of the pet. However, continued research provides hope that one day those who fall victim to allergies will have alternatives or even a cure. For example, Cornell University’s College of Veterinary Medicine supports Elia Tait Wojno, Ph.D. and her 2015 study comparing blood samples and immune cells in allergic dogs and healthy dogs. She hopes to discover if a small blood sample from a dog can determine an allergic disease. If conclusive, it will allow initial treatments to begin much sooner.
Meanwhile, veterinarians remain committed to helping patients, thankful that allergy relief for dogs has progressed within recent years and environmental allergy meds for dogs are more readily available. In addition, pet owners can feel more secure knowing that Veterinary Dermatology is steadfast and continues to advance. Therefore, while it may be a chronic condition, dogs do have the support needed to find comfort and relief via advanced diagnostics and treatments specifically for dog allergies.
- Carol S. Foil, DVM, MS, Diplomate A.C.V.D. (2007, June 9). Itching and Allergy in Dogs. Retrieved from http://www.veterinarypartner.com/Content.plx?A=2604%27
- Laura Simpson, Michigan State University Veterinary Medical Center. Canine Food Allergies. Retrieved from https://cvm.msu.edu/hospital/services/nutrition-support-service-1/client-education/canine-food-allergies
- Canine Health Foundation. Alopecia. Retrieved from http://www.akcchf.org/canine-health/your-dogs-health/disease-information/alopecia.html
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- The Skin Vet Clinic (2012). Food Allergy. Retrieved from http://www.skinvetclinic.com/foodallergy.html
- Thierry Olivry, DrVet, PhD, DipECVD, DipACVD (2010). Treatment of Atopic Dermatitis in Dogs: New International Standard of Care. Retrieved from http://www.cvm.ncsu.edu/conted/documents/Olivry-January2012VMF.pdf
- American College of Veterinary Dermatology (2013). Atopic dermatitis (Environmental Allergy). Retrieved from http://www.acvd.org/pages/category.asp?id=29
- VCA Hospitals. Pruritus - Itching and Scratching in Dogs. Retrieved from http://www.vcahospitals.com/main/pet-health-information/article/animal-health/pruritus-itching-and-scratching-in-dogs/861
- Dermatology for Animals. (2015) Serology vs. Intradermal Allergy Testing. Retrieved from http://www.southernazvets.com/docs/Allergy_Testing_and_Desensitization%20new.pdf
- Cornell University College of Veterinary Medicine (2015, March). Spotlight: On National Puppy Day, how Baker Institute scientists are helping dogs. Retrieved from http://www.vet.cornell.edu/Baker/News/nationalpuppyday2015.cfm
- Shrum, Steve. DVM (2015 April 17). Interview.