Can Dogs Have Allergies? 

 

Yes, dogs can get allergies just like humans do. Dog allergies are often caused by the allergens found in pollen, animal dander, plants, and insects, but dogs can also be allergic to food and medication as well. These allergies can cause symptoms such as excessive itching, scratching, and grooming; rashes; sneezing; watery eyes; paw chewing; and skin inflammation. In some cases, dogs have conditions, such as atopic dermatitis, that is associated with and may be caused by allergies.

 

Atopic Dermatitis in Dogs

 

Atopic dermatitis is an inflammatory, chronic skin disease associated with allergies. In fact, this is the second most common allergic skin disease in dogs. These allergic reactions can be brought on by normally harmless substances like grass, mold spores, house dust mites, and other environmental allergens.

 

Dogs normally show signs of the disease between 3 months and 6 years of age, though atopic dermatitis can be so mild the first year that it does not become clinically apparent before the third year.

 

Despite the fact dogs are more prone to atopic dermatitis than cats, it does occur in felines. If you would like to learn more about how this disease affects cats, please visit this page in the PetMD health library.

 

Symptoms and Types

 

Often symptoms associated with atopic dermatitis progressively worsen with time, though they become more apparent during certain seasons. The most commonly affected areas in dogs include the:

 

• Ears
• Wrists
• Ankles
• Muzzle
• Underarms
• Groin
• Around the eyes
• In between the toes

 

The signs associated with atopic dermatitis, meanwhile, consist of itching, scratching, rubbing, and licking, especially around the face, paws, and underarms.

 

Causes

 

Early onset is often associated with a family history of skin allergies. This may lead the dog to become more susceptible to allergens such as:

 

• Animal danders
• Airborne pollens (grasses, weeds, trees, etc.)
• Mold spores (indoor and outdoor)
• House dust mite

 

Diagnosis

 

Your veterinarian will want a complete medical history to determine the underlying cause of the skin allergies, including a physical examination of the dog.

 

Serologic allergy testing may be performed, but it does not always have reliable results. The quality of this kind of testing often depends on the laboratory which analyzes the results. Intradermal testing, whereby small amounts of test allergens are injected in the skin and wheal (a red bump) response is measured, may also used to identify the cause of your pet’s allergic reaction.

 

 

Dermatologic Food Reactions in Dogs

 

Dermatologic food reactions are non-seasonal reactions which occur following ingestion of one or more allergy causing substances in an animal’s food. The physical reaction is frequently excessive itchiness, with resultant excessive scratching at the skin.

 

While the pathogenesis of these reactions is not fully understood, immediate reactions and delayed reactions to food are thought to be due to a hypersensitive immune response.  On the other hand, food intolerance is a non-immunologic idiosyncratic reaction due to the metabolic, toxic or pharmacologic effects of the offending ingredients. Since it is not easy to distinguish between immunologic and idiosyncratic reactions, any negative response to food is generally referred to as an adverse food reaction.

 

Symptoms and Types

 

• Non-seasonal itchiness of any body location
• Poor response to anti-inflammatory doses of glucocorticoids generally suggests food hypersensitivity
• Vomiting
• Diarrhea
• Excessive gut sounds, passing of gas, and frequent bowel movements
• Malassezia dermatitis (fungal skin infections), pyoderma (bacterial skin infections), and otitis externa (inflammation of the outer ear)
• Skin plaques – broad, raised flat areas on the skin
• Pustules – pus-containing raised skin inflammations
• Erythema – redness of the skin
• Crusts – dried serum or pus on the surface of a ruptured blister or pustule
• Scale – flakes or plates of dead skin on the skin’s surface
• Self-induced baldness due to scratching
• Abrasions/sores on the skin due to scratching
• Leathery, thick, bark-like skin
• Hyperpigmentation – darkening of the skin
• Hives – swollen or inflamed bumps on the skin
• Giant wheals (elongated marks) on the skin
• Pyotraumatic dermatitis – infection of the skin wounds due to scratching excessively, and bacteria entering the wounds

 

Causes

 

• Immune-mediated reactions – result of the ingestion and subsequent presentation of one or more glycoproteins (allergens) either before or after digestion; sensitization may occur as the food passes into the intestine, after the substance is absorbed, or both
• Non-immune (food intolerance) reactions – result of ingestion of foods with high levels of histamine (an antigen known to cause immune hypersensitivity) or substances that induce histamine either directly or through histamine-releasing factors
• It is speculated that in juvenile animals, intestinal parasites or intestinal infections may cause damage to the intestinal mucosa, resulting in the abnormal absorption of allergens and subsequent sensitization to some ingredients

 

 

Diagnosis

 

Your veterinarian will perform a complete physical exam on your dog, including a dermatological exam. Non-food causes of dermatologic disease should be ruled out. Your veterinarian will order a blood chemical profile, a complete blood count, a urinalysis and an electrolyte panel to rule out other causes of disease. You will need to give a thorough history of your dog’s health, onset of symptoms, and possible incidents that might have preceded this condition, especially regarding any changes in diet, and any new foods added to your dog’s diet, even if temporary.

 

Food elimination diets are advised for dogs thought to be suffering from adverse food reactions. These diets typically include one protein source and one carbohydrate source to which the dog has had limited or no previous exposure to. A clinical improvement may be seen as soon as four weeks into the new diet, and maximum alleviation of clinical signs may be seen as late as thirteen weeks into the food elimination diet.

 

If your dog improves on the elimination diet, a challenge should be performed to confirm that the original diet was the cause of disease and to determine what ingredient in the original diet triggered the adverse reaction.

 

Challenge: feed your dog with the original diet. A return of the signs confirms that something in the diet is causing the signs. The challenge period should last until the signs return but no longer than ten days.

 

If the challenge confirms the presence of an adverse food reaction, the next step is to perform a provocation diet trial: going back to the elimination diet, begin by adding a single ingredient to the diet. After waiting a sufficient amount of time for the ingredient to prove either agreeable or adverse, if there is no physical reaction, move on to adding the next ingredient to your dog’s diet. The provocation period for each new ingredient should last up to ten days, less if signs develop sooner (dogs usually develop signs within 1–2 days). Should symptoms of an adverse reaction develop, discontinue the last added ingredient and wait for the symptoms to subside before moving forward to the next ingredient.

 

The test ingredients for the provocation trials should include a full range of meats (beef, chicken, fish, pork, and lamb), a full range of grains (corn, wheat, soybean, and rice), eggs, and dairy products. The results of these trials will guide your selection of commercial foods, based on those that do not contain the offending substance(s).

 

 

By Jessica Remitz

 

Hives (Urticaria) and a swollen face (Angioedema) are commonly the result of an allergic reaction in dogs. Similar to humans, when a dog is exposed to one a particular allergen, the immune system reacts—or in most cases, overreacts—and causes a hypersensitive state. Hives in dogs are usually not life threatening, but it is important to seek veterinarian care as soon as possible to treat the condition.

 

Causes of Hives in Dogs

 

“There are many different allergens that can cause hives,” says Yvonne Szacki, DVM of Park Slope Veterinary Center in Brooklyn, New York. Common causes of hives or swelling of the face include:

 

– Insect stings or bites, including bee stings and spider bites.

– Vaccines, primarily following an injection of a vaccine, like rabies or Bordetella (also known as Kennel Cough). 

– Food allergies.

– A chemical reaction, primarily to insecticides used to treat grass.

– Plants, including poison ivy or oak.

– According to renowned veterinarian and medical journalist Dr. Jeff Werber of Los Angeles, California, “Nearly any allergen that your pet is hypersensitive to can cause hives.”

 

Signs and Symptoms of Hives in Dogs

 

“The degree to which a pet suffers from hives depends on what the irritant or allergen is and the degree to which your pet is affected by it,” Werber says, adding, “Two dogs can be exposed to the same allergen and have extremely different reactions from each other.”

 

Symptoms of hives in dogs can include:

 

– Medium to large areas of redness and swelling on the face, abdomen, and legs.

– Swelling around the muzzle.

– Swelling around the eyes, which can cause them to close.

– Excessive scratching.

– Drooling, if the muzzle starts to swell.

 

Similarly to humans, a dog’s skin will often break out in raised, circular lumps and bumps, “But the reaction can become more severe if left untreated and could lead to a dog’s throat closing,” Werber notes.Because hives are so itchy, your dog may begin scratching excessively, which can also make the reaction worse. “The more the animals is reacting, the more they start scratching themselves and contribute to the trauma of the skin,” Werber says. “Think of it as getting terrible mosquito bites then scratching them all at once—it makes it worse than the bite was in the first place.”

 

Treatment for Hives in Dogs

 

Hives are generally treated with the appropriate dose of antihistamines, such as Benadryl or a steroid, depending on the severity of the reaction. It is not uncommon for the hives to resolve on their own once the allergen has moved through the body, but, according to Szacki, “[It] can take between 24 and 72 hours to clear.” Weber advises that, “Using ice or a cold towel to soothe your dog’s skin can also help them to feel better and limit excessive scratching.”

 

For first-timers, Werber recommends seeing a veterinarian immediately, as failure to treat hives can lead to a more serious reaction as the allergy progresses to other parts of the body.  Pet parents that have dealt with hives before may be able to manage the condition from home, depending on if their dog has been exposed to the same allergen twice and they have instructions from their veterinarian. If you are administering Benadryl from home, Werber suggests administering one milligram per pound.

 

How to Prevent Hives in Dogs

 

“The best way to prevent a recurrence of hives in your pet is to avoid exposing your dog to the allergen that caused the reaction and to keep Benadryl on hand at home,” Szacki says.

 

Werber adds, “If you have identified what your pet has reacted to in the past, particularly for a reaction to a vaccination, you can also pre-treat for the condition. With a reaction to a vaccination, you can give the dog a shot of Benadryl prior to the vaccination, wait 10 to 15 minutes, and then safely give them the injection.”

 

Fortunately, most cases of hives in dogs are just allergic reactions, so there’s no need to panic if your canine does have a breakout. Just be sure to see a veterinarian and follow their advice for appropriate care.