Cat scratching itself on a bed

If your cat has been sneezing, scratching, or coughing, this may be a sign that they have allergies.1 While it can be tempting to reach into the medicine cabinet to relieve their symptoms, it is always a good idea to speak with your veterinarian before giving your cat any human medications. In this article, I will review the symptoms and causes of allergies in cats and what to do if you suspect your cat has allergies.

What are allergies in cats?

Cats can get allergies, just like people! Allergies in cats are most commonly caused by fleas, pollen, or an ingredient in the food.2 The most common symptoms of cat allergies include scratching or sneezing.3 The key to addressing cat allergies is to determine the underlying cause of your cat’s allergies. A veterinarian can help you determine why your cat is having allergies, so you treat the underlying cause.

How can you tell if your cat has allergies?

Cat itching from allergies

Cats with allergies most often demonstrate dermatological (skin) symptoms.4 Often, a cat with allergies will be itchy, lose hair, and may even develop a rash on their skin.5 Cats may also develop sneezing or a runny nose from allergies. Some cats may develop asthma secondary to allergies in the environment.6 Additionally, some cats that have food allergies may have GI symptoms including vomiting and diarrhea.7

The most common symptoms of allergies in cats include:

  • Itching and scratching
  • Hair loss
  • Skin rash
  • Recurrent ear infections
  • Excessive grooming
  • Sneezing
  • Runny nose
  • Coughing or wheezing
  • Vomiting or diarrhea

What are the most common allergies in cats?

1. Flea Allergies

One of the most common allergies seen in cats is flea allergies. Fleas are extremely common and can cause your cat to get itchy, lose hair, and develop rashes.8 Even one flea can cause a cat to have a severe allergic response. This is why it is important to treat your cat for fleas once per month with a quality flea preventative even if you don’t spot any fleas on your cat.

2. Food Allergies

Another common cause of allergies in cats is food allergies. The most common food allergies in cats include allergies to chicken, beef, fish, dairy, and eggs, so your vet may want to place your cat on a special novel protein diet.9 Prescription cat allergy diets are designed to limit the number of ingredients that may cause your cat to have symptoms. Unlike people, it is uncommon for pets to have allergies to grain, but there are many different grain-free cat foods also available.10

3. Environmental Allergies

If your veterinarian has ruled out flea and food allergies, then your cat may have environmental allergies also known as feline atopic dermatitis.11 The most common environmental allergies in cats are dust mites, pollen, mold, and other airborne allergens.12 Symptoms from environmental allergies can occur year-round or seasonally.13 You may be wondering, “can indoor cats get seasonal allergies too?” Yes, even indoor cats can get seasonal allergies!

How do you treat a cat with allergies?

Giving a cat medicine by mouth from a syringe

1. Administer Monthly Flea Preventative

The first step in treating a cat with allergies is to ensure that you are giving your cat a monthly flea preventative. Even if you do not see fleas on your cat, I still recommend giving monthly flea prevention to any cat with allergies. My favorite products include:

2. Try a Special Diet

You may be wondering, “what food is good for cats with allergies?” If I suspect that one of my feline patients has a food allergy, I usually recommend a prescription veterinary diet. These diets contain a novel protein or a hydrolyzed protein that your cat is less likely to have allergies to. Here are a few of my favorite prescription diets:

3. Allergy Medications

Your veterinarian may prescribe allergy medication for your cat to relieve their symptoms. Never administer any over-the-counter medications to your cat unless you have consulted first with your veterinarian. Many human medications can be dangerous for cats.14 Your veterinarian may recommend the following cat allergy medications that may be helpful, especially for environmental allergies in cats:

  • Steroids such as prednisone or prednisolone
  • Atopica
  • Allergy injections

4. Avoid Irritating Substances

If your cat has been diagnosed with allergies, try to keep your house clear of allergens.  I recommend frequently changing your air filters and avoiding smoking in the house. Dust with a damp cloth regularly to reduce the amount of dust in your home. It is also recommended to vacuum the house regularly with a HEPA filter vacuum cleaner. You may also consider keeping your windows closed, especially during allergy season when the pollen counts in your area are high.

5. Try Fatty Acids

Fatty acids can help reduce symptoms of allergies in many cats. Fatty acids may help to decrease skin inflammation leading to reduced levels of itching and scratching.15 I often advise owners to give their allergic cats a daily fatty acid supplement. Fatty acids are most easily administered by placing the liquid directly on your cat’s food. Here are a few fatty acid supplements that I most often recommend to pet owners:

Final Thoughts

Allergies in cats are extremely common and can become very frustrating to both you and your feline friend. For the best treatment recommendations, visit your veterinarian so they can determine the underlying cause of allergies in your cat. Your veterinarian can provide individualized treatment recommendations so your cat can get quick relief from their allergy symptoms.

  1. VCA Hospitals. Allergies in Cats. Accessed March 28, 2021.
  2. Mission Vet. What Are the Most Common Allergies in Cats? Accessed March 28, 2021.
  3. VCA Hospitals. Allergies in Cats. Accessed March 28, 2021.
  4. Noli C. Dealing with feline allergic skin disease. Published September 17, 2018. Accessed March 28, 2021.
  5. O’Dair H, Markwell PJ, Maskell IE. An open investigation into the etiology in a group of cats with suspected allergic skin disease. Vet Dermatol. 1996;7:193–202. Accessed March 28, 2021.
  6. Cornell Feline Health Center. Feline Asthma: What You Need To Know. Updated July 2014. Accessed March 28, 2021.
  7. Barnette C. Food Allergies in Cats. Accessed March 28, 2021.
  8. Cornell Feline Health Center. Flea Allergy. Accessed March 28, 2021.
  9. Cummings Veterinary Medical Center at Tufts University, Clinical Nutrition Service. What every pet owner should know about food allergies. Published January 27, 2017. Accessed March 28, 2021.
  10. Epperley LA. What Vet Nutritionists Have to Say About Pet Food Allergies, Grains. Published August 30, 2012. Accessed March 28, 2021.
  11. Bajwa J. Atopic dermatitis in catsCan Vet J. 2018;59(3):311-313. Accessed March 28, 2021.
  12. Miller WH, Griffin CE, Campbell KL. Muller & Kirk’s Small Animal Dermatology. 7th ed. St. Louis, Missouri: Elsevier; 2013. pp. 388–392. Accessed March 28, 2021.
  13. Bajwa J. Recognizing and Treating Pollen Allergies in Cats. Published April 10, 2018. Accessed March 28, 2021.
  14. Pet Poison Helpline. Top 10 Human Medications Poisonous to Pets. Accessed March 28, 2021.
  15. Cornell Feline Health Center. The Challenge of Skin Disorders. Accessed March 28, 2021.