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Allergies in dogs: does my dog have allergies? reading-time-icon 2 min read


As anyone who suffers from allergies will know, the sneezing, sniffing, watering eyes and skin rashes that accompany allergies can make life pretty miserable – and the same is true for our pets.

Allergies are commonly triggered when your dog’s immune system overreacts to a foreign substance.

These substances – known as allergens – fall into four categories: food, parasites (usually fleas), inhalant (airborne) allergens and contact allergens.

Each has its own signs and symptoms, but the main hints that your dog may be suffering from an allergy include the following:

Signs and symptoms of allergies in dogs: 

  • Coughing
  • Sneezing
  • Wheezing
  • Difficulty breathing 
  • Red, watery eyes
  • Itchy, red skin
  • Sore ears
  • Skin rashes
  • Sickness
  • Diarrhoea

What is flea allergy, and how is it treated?

Flea saliva contains multiple allergens that can trigger an allergic reaction in dogs. Most dogs are only mildly irritated by flea bites, but a dog who is allergic can have such a severe response that they scratch or chew at the bitten area until they’ve removed large chunks of hair.

Flea allergy dermatitis (FAD) is the most common allergic condition in dogs, and causes severe itching that’s triggered by flea saliva on the dog’s skin. 

Once fleas have taken hold of your dog, and your home, they’re tricky blighters to eliminate, so the best treatment is prevention. It’s vital to get into a regular routine of protecting your dog and your home against fleas. Your vet can recommend the best method.

What are food allergies, and how are they treated?

Dogs can develop food allergies without warning at any time – even when you’ve fed them the same product for years. Because food allergies are one of the most common causes of allergic dermatitis in dogs, it’s important to feed your pup a balanced diet, and to change what you feed them from time to time, to avoid over-exposure.

The most common causes of food allergies include eggs, wheat, fish, pork, dairy, and beef. Symptoms include itchy paws, armpits & ears, and digestive disorders – often indicated by vomiting and diarrhoea.

Your vet may recommend food allergy testing, and may suggest an elimination or hypoallergenic diet. 

Read more about food allergies in dogs.

What are inhalant allergies, and how are they treated?

The main symptom of inhalant allergies in dogs – also called seasonal allergies – is severe itching. Dogs can be sensitive to pollen, mould, mildew and dust mites – even cigarette smoke – in the same way humans can. 
If the allergy is seasonal, your dog may scratch for just a couple of weeks at a time. Your vet may recommend treatment with anti-inflammatory medication or a medicated shampoo. In some cases, they may suggest a preventative vaccination. 

What are contact allergies, and how are they treated?

Contact allergies occur when your dog’s skin comes into contact with a substance they’re hypersensitive to, such as wool bedding or flea collars. Once you’ve worked out what triggers the allergy, it’s easy to avoid the reaction – simply keep the allergen away from your dog and the itching will subside. 

“Dogs can develop food allergies without warning at any time – even when you’ve fed them the same product for years.”

Advice on dog allergies

For expert advice and treatment on dog allergies, contact your local vet.

Find your nearest vet using our Find a Vet page, or speak to a vet online using Online Vets.