AllergiesHave you noticed your pet itching, scratching, chewing, or licking excessively? Does he sneeze frequently and shake his head or rub his face often? These may be signs that your pet has allergies. Just like us, your pet can be allergic to a variety of substances he breathes in, eats, or encounters within the environment.

Types of Allergies

There are different types of allergies that your dog or cat can experience: flea, food, and environmental allergies.


Flea allergies are the most common allergy experienced in pets. This condition is a hypersensitivity to the proteins or antigens found in flea saliva. When a flea bites a cat or dog, a small amount of saliva is released and triggers a reaction from your pet’s immune system causing extreme itchiness and skin irritation throughout the body not only at the bite.


Food allergies are the result of an immune response and are different from a food sensitivity or intolerance, though some symptoms can be similar. Food allergies can result in a range of symptoms from facial swelling, itchiness, and gastrointestinal symptoms such as vomiting and diarrhea. In severe cases, anaphylaxis may occur. Food sensitivities and intolerances are generally less severe and often limited to digestive problems.

Beef, dairy, wheat, egg, chicken, lamb, and soy are the most common food allergens for dogs while beef, dairy, and fish are more common in cats.


Environmental allergies are from allergens present in your pet’s environment and include dust, fungi, pollen, mold, plants, grass, mildew, perfumes, cleaning products, and smoke. Though seasonal allergies are environmental, some of the allergens may be present all year-round and result in constant irritation. Environmental allergies do not have to be from close contact as your pet can also inhale allergens.

Allergic contact dermatitis is another form of allergic reaction that is often caused by chemicals or products that encounter your pet’s skin. This can include detergents, soaps, natural and synthetic fibers, paint, cleaning products, and insecticides. Excessive itching, redness, and irritation are the most common symptoms on and around the site of contact. Secondary symptoms may appear such as hair loss, sores, scabbing, and hot spots.

Signs and Symptoms

Symptoms of allergies can vary depending on the cause and type of allergy. The following signs may be a sign of an allergic reaction.

  • Constant licking or grooming
  • Diarrhea
  • Ear infections
  • Excessive itchiness
  • Facial swelling
  • Hives
  • Itchy ears
  • Red, inflamed skin
  • Runny eyes
  • Sneezing
  • Vomiting
  • Difficulty breathing

It is important to note that these symptoms can also be signs of another condition.

Your pet may not present all of the symptoms listed above in his allergic reaction. A pet that develops anaphylactic shock from a food allergy will display different symptoms from a pet with a flea allergy.

Diagnosing Your Pet’s Allergies

Diagnosing allergies can be difficult as the symptoms of allergies could be caused by another medical condition. It is important if you suspect your pet has allergies to contact your vet so that they can diagnose your pet accurately and begin treatment immediately.

Your vet will review your pet’s medical history and complete a thorough examination. Allergy testing may be conducted with a blood or skin test. For a blood test, a sample of your pet’s blood will be sent to a laboratory for evaluation. For a skin test, small injections can be given to your pet just under the skin to see if a reaction develops. Both tests may be conducted to gain a better understanding of your pet’s allergies.

It is important to note that sometimes allergy testing may not always be a reliable method of diagnosing. Blood and skin tests can be ideal for determining some environmental allergies but are unreliable for food allergies. Food allergies may require eliminated diet trials to determine the cause of your pet’s reaction. Flea allergies can usually be diagnosed by evidence of a flea infestation.


Allergy treatment will depend on the cause of the allergy and the condition of your pet:

  • Flea allergy treatment is aimed at reducing symptoms until the fleas are eliminated. It is important to not only treat your pet for fleas but also his environment.
  • For food allergies, once your diet trial determines the allergens adjustments must be made to your pet’s diet to ensure optimal health. Be sure to consult with your veterinarian before making any changes to your pet’s diet.
  • For environmental and seasonal allergies there are a variety of treatment options available. Prescribed antihistamines or corticosteroids can help to manage symptoms. Topical ointment, ear drops, eye drops, and formulated shampoos can also alleviate itchiness and minimize skin irritation to help prevent excessive licking or scratching.

In more severe cases, allergy shots can help to desensitize your pet from the allergen with repeated exposure. This is beneficial in the case of seasonal or environmental allergies as symptoms are significantly reduced.

If your pet has developed a second infection due to excessive scratching or grooming, your vet will also provide additional treatment.


The best course of treatment is to avoid allergen triggers and prevent your pet from encountering them. Here are some great allergy prevention methods you can take for your pet:

  • Avoid smoking and using harsh chemicals or strong-smelling products in your home
  • Bathe your pet with allergenic shampoo if needed to relieve itching
  • Keep your home clean to prevent dirt and dust from building up
  • Use flea and tick control regularly
  • Wash your pet’s bedding and favorite toys often

If you suspect your pet may have allergies, please contact our office to schedule an appointment. Though humans can outgrow allergies or learn to avoid certain allergens, your pet needs your help in living a healthy life and we are here to offer our expertise in your pet’s care. For more information on pet allergies or to schedule an appointment, contact Blue Cross Veterinary Hospital today.

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