ACHOO! - It's an allergy

ACHOO! - It's an allergy

Allergies – those pesky reactions that can leave you itchy, sneezy, sick, or worse. Your pet could suffer from these symptoms too, so let’s talk about what it means.  


Allergies develop when the immune system overreacts to what is called an Antigen. Prior exposure to this antigen must have occurred to prime the immune system.  

In dogs, the common types of allergies or hypersensitivities include:  

  • flea bites  
  • foods such as protein in beef/lamb/chicken/dairy products (this could be a true allergy or more commonly a hypersensitivity)  
  • something in the environment such as house dust mites, dust, pollens, grasses, moulds, or human skin, so-called Environmental Allergies. 
  • Allergies that are not flea bite allergies are generally termed Atopy.  

Allergies can cause itchiness, scratching, rubbing, licking, red areas of skin, tummy, muzzle, armpits, groins, tail base, around the eyes or between the toes, ear problems, sneezing, watery eyes, diarrhoea, and vomiting.  

A secondary bacterial or yeast infection (which can sometimes be smelled as a yeast-type smell) on the skin or in the ears can then develop as the skin barrier is altered.   

There are other causes of skin disease and irritation such as other parasites, Ringworm (fungal infection by dermatophytes), auto-immune disease, and others. To investigate skin problems in dogs, tests such as skin scrapings, skin biopsies, swabs for culture of bacteria or dermatophytes, blood tests for broad categories of allergens or skin tests for individual allergies (the latter usually done by a skin specialists) can be performed.  

The blood tests for food allergy or hypersensitivity are not the most reliable, so instead, we could use an exclusion diet as a trial to see if a food allergy is present. This can be done before all the other tests and involves removing all food the dog has eaten previously from their diet. The trial can last for 6-12 weeks to see if this helps the skin improve


If intradermal skin tests shows specific allergies, then there is the possibility of desensitisation with repeated, or drops, of larger amounts of the allergens over several weeks and months which may help.  

Common breeds to have allergies, which suggests a genetic component, include:  

  • Golden Retrievers 
  • Poodles
  • Shih Tzus
  • Cocker Spaniels
  • Bulldogs and Bull breeds


Managing the problem involves trying skin supplements, shampoos, foams, or sprays to help irritation and reduce secondary bacterial and yeast infections. Prescription medications can help to reduce irritation and inflammation such as Apoquel, Atopica or Prednisolone (a corticosteroid). Sometimes antibiotics are also required. 

Allergies will often mean a lifetime of managements if several allergens are identified to be bothering your pet, especially if fleas and diet have been ruled out. Hopefully, by understanding how to identify and care for allergies, we can improve the welfare of our pets.