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How Does Cat Allergy Testing Work? Test Types, Signs & FAQ

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Last Updated on November 16, 2023 by Ashley Bates

Whether your cat is displaying signs of allergies, or you just want to get ahead of things, you might wonder how exactly allergy testing works. After all, allergy testing can sometimes be lengthy and very much trial and error.

Here, we will discuss the different kinds of allergy testing and how veterinarians determine the allergy trigger. Keep in mind that this is in no way a substitution for medical advice, and you should always seek your vet’s attention if you suspect allergies in your cat.

Click below to jump ahead:

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How Does It Work?

Allergies are common in felines and can stem from numerous sources. Your cat could be allergic to something in their environment or diet. If your vet suspects your cat might have allergies, they will recommend a method of allergy testing. Testing typically involves taking a skin or blood sample to analyze it further.

Usually, the process is relatively fast, causing minimal pain to your pet. Once your vet determines the underlying cause of the allergic reaction, they will give you a care plan to address it appropriately.

You can buy allergy testing kits online and perform them from the comfort of your home. Tests might be less accurate depending on brand and method, so always get a professional recommendation before selecting this option.

Even if you do get a positive result from an at-home test, it will require follow-up care with your vet—so never assume it’s a one-stop shop or a way to cut corners.

3 cat face dividerWhat Are the Different Types of Allergy Tests for Cats?

Allergy testing in cats uses two techniques, which are intradermal skin testing or RAST testing. Each method has its pros and cons, so it will greatly depend on the individual cat.

Intradermal Skin Testing

Many vets revere intradermal skin testing as the gold standard for determining atopic dermatitis. Veterinary dermatologists are the only ones qualified to perform this test, so it’s a specialized field.

Even though this test is incredibly accurate, it’s not available to all pet parents. Your vet will likely have to refer you to a specialist. Not only can testing be much more expensive this way, but it can also take a lot of work to get in for an appointment.

Intradermal testing is typically used to uncover environmental allergies with triggers like weeds, molds, fleas, and other irritants. The veterinary dermatologist will inject 60 different allergens beneath the subcutaneous layer of your cat’s skin during the test.

Before the injection, cats are usually given a mild sedative, as the test can be somewhat painful. The injectable serum used is completely tailored for your cat, meaning it will be different than those given to others.

It takes roughly an hour to validate intradermal testing. If a bump or hive forms where the serum was injected, your cat has some environmental allergy. Your vet will devise a plan for treatment after the results are determined.

cat blood sample
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Radioallergosorbent Testing (RAST)

RAST Testing requires a single blood sample and can be drawn by a veterinarian during a routine visit. Many prefer this testing because you don’t need a specialized doctor.

RAST is very efficient and quick. This testing measures an allergy antibody in the system. If your cat is allergic to a specific kind of food or environmental trigger, the RAST test will show positive or negative. If your cat has a negative test, it is unlikely that it is suffering from an allergy.

If they are displaying signs of an allergy but have a negative test for allergies, your vet will likely look at other areas to determine the underlying cause. A positive result, on the other hand, points to an underlying issue that you will address with your veterinarian to discuss the best course of treatment.

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Where Is It Used?

For the most accurate results, cat parents take their pets to the veterinarian for testing. However, you can also buy testing kits online. These tests might take longer, as you need to collect the samples and have them sent into a laboratory for evaluation.

It might be a more cost-friendly alternative if you’re looking to avoid high vet costs. Still, if the allergy testing at home shows some allergic reaction, we recommend following up with your veterinarian to solidify your findings.

a cat in a veterinary clinic being examined by a doctor
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cat paw dividerThe 4 Types of Allergies in Cats

Allergies don’t come from one particular source. Your cat can be allergic to many potential allergens, so you should know the problem areas. Here are the most common.

1. Food Allergies

Food allergies are a widespread problem for cats. They can be allergic to a number of ingredients used in their own diets. They can also be allergic to other food items around the house.

2. Insect/Mite Allergies or Flea Allergy Dermatitis

Cats can have allergic reactions to parasites like ticks, fleas, and skin/ear mites. A protein present in the parasite’s saliva causes irritation in the cat’s skin.

3. Atopic/Environmental Allergies

Cats can be allergic to many different kinds of mold and dust around the home. So, if your home is particularly dusty, you might need to upkeep it better to avoid these types of allergies.

Believe it or not, cats, like us, can be allergic to plants. This can stem from trees, grass, and weeds, or a combination of them.

Surprisingly, cats might show allergies to certain farm animals—like sheep and cattle. If a barn cat is experiencing irritation, either animal could be the culprit.

4. Contact Allergies

A rare condition in cats involving delayed hypersensitivity reaction when the skin is in contact with pollen, yeast, or mites.

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What Is Hyposensitization and Why Is It Effective?

Hyposensitization treatment is a very effective method of easing allergies in your cat. The process includes giving your cat a small quantity of triggering allergens through injections or oral medications. Depending on your cat’s specific allergy, you typically give one injection or oral treatment once every 1 to 4 weeks.

The goal here is to build immune tolerance in the body. The general outcome of this treatment method is good, improving 60% to 80% of cats’ overall reactions. Some cats take longer than others to show the benefit and others require lifelong therapy depending on the severity of the allergy.

A medicine given to a cat
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cat paw dividerRAST vs. Intradermal Testing: Pros & Cons

Both types of testing certainly have their pros and cons. We’re going to give you a breakdown of each so you can get a better understanding of what to expect.

Intradermal Testing Pros & Cons

  • Extremely Accurate
  • Considered gold standard by professionals
  • Visual results
  • Wide range of allergens tested
  • Lengthy test
  • Requires sedative
  • Requires specialized veterinary dermatologist
  • Sometimes requires travel
  • Cat must be shaved in an area for monitoring

RAST Testing Pros & Cons

  • Very treatable with hyposensitization
  • Requires only a single blood sample
  • Can be done at a traditional vet’s office
  • At-home testing kits available
  • Notorious for false positives
  • Does not diagnose atopic dermatitis
  • Not efficient at specific diagnoses

3 cat face dividerAllergy Signs in Cats

Allergies can crop up for your cat at any time. The triggers can be innumerable. Allergy testing is so important because it directly answers what is bothering your cat. If you suspect your cat has allergies, veterinarians will assist. But how exactly do you know when to take them in?

Manifestations of allergies include skin irritation, respiratory issues, and digestive system upset.

Signs of allergies include:
  • Skin redness
  • Hair loss
  • Itching
  • Coughing
  • Sneezing
  • Nasal/eye discharge
  • Vomiting
  • Flatulence
  • Diarrhea

If you suspect your cat has allergies, you can reach out to your veterinarian to make an appointment.

What Can Be Mistaken for Allergies?

Your pet should get hands-on care through this process. If your vet determines that they do not, in fact, have an allergy, they can do further testing to evaluate what might be triggering these similar symptoms.

Sometimes, things like food intolerances are mistaken for food allergies. A food allergy in cats can affect both the gut and the skin. These allergies typically stem from an abnormal immune response to protein sources like fish or chicken.

Food intolerances, on the other hand, stem from a specific aspect of your cat’s diet. A sensitive stomach might get irritated if it lacks the proper enzymes to fully digest a particular ingredient in food or if your cat has irritable bowel syndrome.

Your cat might also have something less severe, like seasonal allergies, just like people do. Seasonal allergies are typically easier to treat and don’t require ongoing care.

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Frequently Asked Questions

How much does an intradermal test cost?

Generally, intradermal skin tests cost between $190 to $250, depending on the facility.

How much do RAST tests cost?

RAST tests at a vet’s office usually cost between $200 and $350.

blood samples in test tubes
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How much do at-home tests cost?

At-home cat allergy tests range from roughly $45 to $300, depending on the brand and effectiveness.

How effective is hyposensitization therapy?

As we mentioned previously, hyposensitization therapies for cats to treat allergies are roughly 60% to 80% effective. Some cats must have lifelong therapy, while others only need treatment for a short while before improvements are visible.

How much does allergy treatment cost?

Costs can really vary depending on the severity of your cat’s allergies. However, the average is approximately $50 monthly, translated to roughly $600 annually. This cost can be much lower if you have a health insurance policy in place for your cat.

What are alternatives to treat allergies?

Depending on the type of allergy your cat has, treatment can come with the elimination of specific triggers. For example, if your cat is allergic to trees, you can limit their access outside. Or, if your cat has some type of food allergy, you can give him a specialized diet that eliminates the triggering ingredient.

cat eating food in the bowl
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cat paw dividerImportance of Insurance for Cats

Vet costs just seem to get higher as the years pass. Because the health and wellness of your cat is so crucial, we highly recommend pet insurance. The earlier you opt for pet insurance, the more issues will be covered.

However, if your cat has any diagnosis before getting pet insurance, it will be considered a pre-existing condition and won’t be covered by your chosen policy. If you opt for the health insurance of your choice, you can get everything that you want with a monthly premium that’s in your budget.

That way, if your cat develops allergies anytime you have an active policy, the bulk of the cost will fall onto the insurance company once your deductible is paid. While not all policies cover allergies, you can get free quotes and explore coverage from many different companies on the market.

You can even bundle your cat’s insurance with your existing insurance company, providing they have the option to cover domestic pets. It’s certainly worth checking into and can foot a lot of the cost so you don’t have to.

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If you feel your cat is suffering from allergies, the very first step you need to take is to contact your veterinarian. Now that you’re familiar with the types of testing used to determine allergies, you can go in with an eased mind.

Plus, if finances are an issue, it’s nice to research how much these tests cause so you can plan it for your budget. If you were just curious about allergies but your cat doesn’t seem to be displaying signs yet, we encourage you to check out potential health insurance plans. It’s best to cover your cat before any issues arise so your wallet doesn’t pay the price.

Featured Image Credit: PRESSLAB, Shutterstock

About the Author

Ashley Bates
Ashley Bates
Ashley Bates is a freelance dog writer and pet enthusiast who is currently studying the art of animal therapy. A mother to four human children— and 23 furry and feathery kids, too – Ashley volunteers at local shelters, advocates for animal well-being, and rescues every creature she finds. Her mission is to create awareness, education, and entertainment about pets to prevent homelessness. Her specialties are cats and dogs.

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