Allergies in Your Pet

Did you know that dogs and cats can suffer from allergies, just like a human can? They can be allergic to a wide variety of triggers such as food, pollens, insect bites, even human dander!

Signs of allergies

Regardless of whether allergies are to a food or environmental cause, signs of allergies can be varied:

  • Chewing at paws, red in between toes, dark brown debris or smell in between toes
  • Red ears with bad odour, frequent ear infections
  • Scooting bum
  • Red eyes, clear watery discharge from eyes
  • Sneezing or wheezing
  • Rash or red bumps across the belly
  • Vomiting and diarrhea
  • Hair loss under armpits and thighs, and along the belly
  • And most commonly: Itching!


Pets start to show signs of allergies as early as six months of age, but most pets do not start to develop allergies until they are about two years or older. If a food allergy is suspected, the only way to effectively diagnose this is with something called an ‘elimination diet trial.’ With an elimination diet trial, your pet is fed a hypoallergenic veterinary diet that is made in a facility that is thoroughly cleaned of any possible contaminants, and quality checked to ensure the food does not contain anything that could trigger an allergy. Pets must be on this hypoallergenic diet for eight weeks with no other treats, table scraps, supplements or other additions to their food. After eight weeks if the symptoms of their allergies have improved, we can try feeding the food we suspect they have an allergy to. If their signs flare up at this point, we have confirmation that they do have an allergic reaction to this type of food and it should be avoided in their diet and treats long term.

For environmental allergies, we can refer your pet to a dermatologist who will perform a skin test for the most common type of environmental allergens.


Often pets with environmental allergies are sensitive to many different allergens, so avoiding everything that could cause a reaction is unfeasible. Allergies are rather controlled, either seasonally or year-round with three main types of treatment:

  1. Medications – A variety of medications are available to help treat the symptoms of allergies: Antihistamine, steroid medications, cyclosporine, Apoquel, and Cytopoint are all used to bring down inflammation and reduce itching
  2. Topical shampoos or sprays – to get rid of secondary skin infections and repair the skin barrier
  3. Serum injections – if your pet does go to a dermatologist for allergy testing, the specific antigens that your pet is allergic to can be made into serum and injected in small doses once a week to slowly desensitize your pet, so they are not as reactive to the allergen.

Treatment for allergies is to control symptoms and make your pet more comfortable. Because dogs can be allergic to many environmental allergens, or a combination of food and environmental allergies, avoiding their triggers altogether is usually not possible. Diagnosis and treatment of allergies are, therefore, a journey rather than a destination with a cure at the end.

If you have any questions, give us a call at 519.453.2940.

Written by: Dr. Connie Tuck, DVM