A cat having a veterinary check up

Allergies in cats: does my cat have allergies?

ACHOO! 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 cat’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 cat may be suffering from an allergy include the following:

Signs and symptoms of allergies in cats: 

  • Coughing
  • Sneezing
  • Wheezing
  • Watery eyes
  • Itchy, red skin
  • Sore ears
  • Sickness
  • Diarrhoea

What is flea allergy, and how is it treated?

Flea saliva contains multiple allergens that can trigger an allergic reaction in cats. Most cats are only mildly irritated by flea bites, but a cat 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 and sometimes even skin, making themselves bleed.

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

Once fleas have taken hold of your cat, 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 cat and home against fleas. Your vet can recommend the best method.

What are food allergies, and how are they treated?

Cats can develop food allergies without warning at any time – even when you’ve fed them the same product for years. Food allergies are estimated to be the second most common cause of allergic dermatitis in cats.

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

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

What are inhalant allergies, and how are they treated?

The main symptom of inhalant allergies in cats – also called atopic dermatitis or seasonal allergy – is severe itching. Cats can be sensitive to pollen, mould, mildew and dust mites in the same way humans can.

If the allergy is seasonal, your cat 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 cat’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 cat and the itching will subside. 

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

Advice on cat allergies

For expert advice and treatment on cat allergies, contact your local vet. To find your nearest recommended vet or pet clinic, use our Find a Vet page.