What Are Cats Allergic To?

Cats are allergic to a wide range of substances and factors, ranging from pollens and parasites to food and drugs. Allergies are caused by a deficient immune system, which responds negatively to certain allergens. If your cat shows symptoms of allergies such as sneezing, watery eyes, itchiness, breathing difficulties, rashes or hair loss, you need to detect the cause of allergies. Detecting the allergen is essential in finding an efficient long term treatment.

Inhalant Allergens

The most frequent allergies are caused by airborne substances. Symptoms that a cat with allergies will display include:

  • Pollen (grass, weeds, trees)
  • Dust
  • Mold spores
  • Household chemicals
  • Pesticides or fertilizers
  • Perfumes
  • Smoke
  • Fungi

These allergens can be inhaled or can enter the cat’s system through the skin pores. Some of these allergic reactions will be seasonal, while others are permanent, depending on the cause of the irritation.


Parasites, especially fleas, ticks and ear mites, can cause allergies in felines. Cats are allergic to the saliva of these parasites, which is transmitted to the cat through bites.

Once the parasites are removed, the cat will be allergy free. However, the allergic reactions can persist for up to a week after the parasites are gone.


Cats can be allergic to different insect stings or animal bites. The venom of bees, wasps, snakes and mosquitos can cause irritation. A cat can even develop anaphylactic shock in the most severe cases.


Cats can be allergic to drugs. The most common allergens include penicillin, erythromycin or sulfonamides. Cats can also be allergic to anesthetics, so the pet needs to be tested prior to a surgical procedure.

Contact Allergies

Cats can be allergic to different materials they come in contact with. Materials such as plastic, wool, latex, metals or synthetic fabrics can irritate the cat's skin. A contact allergy will only manifest itself through skin rashes and itchiness, without sneezing or other symptoms.

In case you notice any allergic reactions in your cat, try replacing plastic bowls with ceramic ones, and remove possible allergens from the cat’s environment. Replace the cat’s bedding with some 100% natural materials, such as cotton.


Cats can develop allergies to common food ingredients. The most frequent food allergies in cats are to:

  • Beef
  • Turkey
  • Chicken
  • Corn
  • Corn starch
  • Peas
  • Flour
  • Pumpkin
  • Milk or dairy products
  • Seafood
  • Wheat

It must be noted that food allergies are different from food intolerances. Food allergies cause skin itching, rashes or bumps on the skin. Food intolerances cause vomiting, diarrhea or constipation.

Once the culprit allergen is detected, it must be completely removed form the cat’s diet.

Allergies can occur at any age, but typically not before the age of 2. Cats with a weaker immune system will develop allergies more often. Some sensitive cats will have allergies to several substances or foods. Allergy testing can be done through blood or skin testing. Food trials will be needed to identify food allergies.