When your dog's allergy symptoms are severe, it can affect their quality of life. Regularly licking and biting their itchy skin can lead to frequent skin infections while scratching their itchy ears and shaking their head can lead to hematomas. Dog allergy testing can give you insight into what's causing your dog's symptoms and potentially help you find a solution.
Note that we said potentially. Some allergens are difficult to avoid, so even if you figure out what's causing your dog's symptoms, it may not result in an improved treatment plan.
Before you commit to spending your time, money, and other resources on dog allergy testing, find out which types of testing are available, whether they'll help your dog, and when they're worth the investment.
When Should You Consider Dog Allergy Testing?
Some dog allergy tests are easy to do at home and the cost is within reach for most pet parents. Others require laboratory testing or an appointment with a veterinary dermatologist. We recommend that you work closely with your family veterinarian throughout the allergy testing process. They can help you navigate the different tests and decide on a treatment plan.
Testing for flea allergies and food allergies is relatively easy and inexpensive. So, we recommend that any pet owner whose dog has allergies consider these tests. We'll explain how to do these tests below.
Testing for environmental allergies is much more complex and expensive. Because many environmental allergens can't be avoided, identifying them may not provide an improved treatment plan. We only recommend testing for environmental allergens when pet parents decide to pursue immunotherapy as a treatment for their dog's allergies.
Deciding on Immunotherapy
The first line of treatment for dogs with environmental allergies is usually an antihistamine and a supportive allergy supplement. Antihistamines are inexpensive, easy to administer at home, and effective for many dogs. If your dog's symptoms improve on antihistamines, your vet is unlikely to recommend immunotherapy, and there will be no reason for you to spend money on additional allergy testing.
However, if antihistamines don't help your dog, your vet may recommend a stronger medication, like corticosteroids, or they may recommend immunotherapy.
Corticosteroids are extremely strong drugs that can cause many side effects: They can make your dog more susceptible to infections and lead to increased thirst, urination, nausea, and loss of energy. Corticosteroids typically cost $40–$150 per month. You may be able to give your dog a pill at home, or you may have to take your dog to the vet for monthly injections. If you decide to treat your dog with steroids, you won't need to do allergy testing.
If you decide against corticosteroids, your other options will be immunotherapy. Immunotherapy is a more natural treatment than antihistamines or corticosteroids, and, in some cases, it can completely cure or dramatically improve your dog's allergy symptoms. As part of this treatment, your dog will get regular injections with a small amount of the allergens that affect them. The goal is to teach your dog's immune system not to react to these allergens.
This treatment can be affordable, but it is often time prohibitive. Your dog will need injections every 1–4 weeks. You may be able to do the injections yourself at home, your family vet may offer this treatment, or you may need to go to a veterinary dermatologist.
If you do the injections yourself, it will cost around $5–$10 per 1 mL of allergen treatment. If you take your dog to the vet for injections, you will also have to pay the typical cost of a vet visit — which can range from $50 to $400, depending on your vet. It can take six months to a year to determine if this treatment is working, and some dogs may need ongoing treatment for the rest of their lives.
As pet owners, we each have to decide on the right course of treatment for our dogs. If you decide on immunotherapy, you will need professional dog allergy testing to determine which allergens to treat for. We'll cover what to expect from professional testing below.
Different Types of Dog Allergy Testing
Testing for each of the different types of allergies will differ, and you should only perform one type of allergy test at a time. If you were to test for flea allergies and food allergies at the same time, and your dog's symptoms started to improve, you wouldn't know if the flea test or food test helped.
Each type of test can take 1-2 months to thoroughly complete. For nearly all of these tests, you'll need to take your dog off their current antihistamines or other allergy medication — check with your vet to make sure this is safe for your dog.
It pays to be patient and thorough during allergy testing so that you can feel confident in your results and won't need to repeat any tests. Here's how to perform each type of test.
Testing for Flea Bite Dermatitis
Flea bites are the most common cause of atopic dermatitis, or skin allergies that manifest as hives or red spots on your dog. So, we recommend testing for this allergy first. While you'll need to work with your vet, this type of testing is easy to do and relatively inexpensive. You should expect to spend $50–$60 for a flea comb, shampoo, a flea bomb, and outdoor yard spray, plus $20–$30 per month for ongoing flea medication.
First, use a flea comb to brush your dog's fur close to their skin. Pull the comb up after each stroke and inspect it for fleas — you'll see small black bugs on the comb. Trap any fleas you find in an air-tight container and throw the container away. Even if you don't find fleas, you should continue with the next steps, as fleas can jump on and off dogs. If your dog is only getting occasional bites and isn't suffering from a major infestation, you may not find fleas in their coat.
Next, give your dog a bath using a flea shampoo and let them dry thoroughly. Use a flea bomb to get rid of fleas in your home and carpet. (Make sure to read the directions carefully, and remove yourself and your pets from the house before setting off the flea bomb.) Use an outdoor flea spray to kill any fleas living in your lawn and garden. Then, start your dog on a prescription flea treatment from your vet.
Topical flea treatments are available over the counter, but in scientific studies, prescription oral medications have been more effective at treating and preventing fleas. It's also easy to apply topical treatments incorrectly or bathe your dog too often and reduce the treatment's effectiveness. With oral medications, all you have to do is give your dog a pill.
The medicine will start killing fleas within 48 hours, but if there are any unhatched flea eggs in your environment, it can take up to a month to completely eliminate the flea problem. Any unhatched eggs or larvae that remain after you've treated your dog, home, and yard will be killed by the prescription medication when they become adults and jump on your dog.
Remember to continue giving your dog a monthly prescription flea treatment throughout their life. Even if you've eliminated fleas from your environment, your dog can still contract these parasites from the dog park or from their daily walk.
Once you start giving your dog a prescription flea medicine, wait 1–2 months to see if your dog's allergy symptoms clear up. If they do, you don't need to do any more allergy testing. If not, move on to testing for food allergies.
Testing for Food Allergies
If your test for flea allergies doesn't improve your dog's allergy symptoms, the next thing to test for is food allergies. While food allergies are less common than environmental allergies, they're easier to test for and easier to treat, which is why we recommend you try this line of testing second. This is by far the most inexpensive allergy test — you'll only pay for the food you choose to test with — and the easiest to do on your own at home.
Dogs can be allergic to any food, but the most common foods that trigger an allergic reaction are chicken, beef and dairy products. To test for these and other food allergies, you'll put your dog on an elimination diet.
Start by purchasing a limited ingredient diet (LID) dog food. You can find LID food at most pet stores and will recognize it by the words "limited ingredient" or "LID" on the label. This type of food eliminates many common dog food ingredients, often limiting the number of ingredients in your dog's diet to 10 or fewer.
When you switch your dog from their current food to an LID food, make the change gradually so that you don't cause an upset stomach or diarrhea. Follow this guide and use a dog probiotic or pumpkin for dogs to keep your pet regular during their dietary transition.
Once your dog is eating 100% LID food, the testing officially begins. Keep your dog on the new diet for one month, and be careful not to feed them any treats during this time (unless they're made with the exact same ingredients as your chosen LID food — some brands offer matching food and treat formulas).
If your dog's symptoms start to improve, you can add whole foods back into their diet one at a time to see if they cause a reaction. For example, you can put a few bites of fresh chicken on top of their food to see if that causes their allergy symptoms to return.
If, after a week of feeding chicken, your dog doesn't have an allergic reaction, you can introduce another new food. Repeat this process with one food at a time until you identify what's causing your dog's symptoms.
Some pet parents keep their pets on an LID diet long-term, but we don't recommend this approach. Like humans, dogs benefit from a variety of proteins, whole grains, and dog-friendly fruits and veggies. It can take time to identify a specific food allergen, but the additional testing will ensure your dog can continue to enjoy a varied and nutrient-rich diet.
If your dog's symptoms don't improve on an LID diet, you may want to repeat the test with a second LID formula that includes completely different ingredients from the first formula you used. If your dog's symptoms improve on the second diet, you'll know they're allergic to one of the ingredients in the first LID formula.
If your dog's symptoms still don't improve, their allergies are likely caused by environmental factors. In this case, you should talk to your vet about putting your dog on an antihistamine or testing for environmental allergens so you can start immunotherapy treatment.
Testing for Environmental Allergies
Environmental allergens are a common culprit behind atopy (those hive-like skin allergies) and sneezing in dogs. A number of environmental factors can cause allergies, including dust mites and pollen.
As we mentioned, many of these allergens are unavoidable, so testing for environmental allergies is usually only worth your time and energy if you plan on pursuing immunotherapy to treat your dog's allergies.
All of the tests for environmental allergies require a veterinarian or laboratory for analysis. Here are the options for environmental allergy testing.
At-Home Test Kits
Because they don't require a vet appointment, at-home allergy testing is becoming more popular with pet owners. At-home test kits typically cost between $100–$300. To perform the test, you'll use a swab to collect a saliva sample from inside your dog's cheek. You'll package the sample and send it back to the test manufacturer.
The manufacturer will run saliva tests, looking for specific allergen antibodies in your dog's saliva. Manufacturers of at-home allergen and intolerance tests claim their kits can detect everything from severe allergies to mild intolerances.
In addition to environmental allergens, these tests look for food sensitivities. However, according to the Cummings Veterinary Medical Center at Tufts University, saliva tests don't produce accurate test results for food sensitivities, and they can lead to a lot of false positives. You'll get much more accurate results using an elimination diet to diagnose food sensitivities.
Recent research into saliva tests for humans also calls into question the accuracy of environmental test results. Ultimately, these tests are still unproven. They may one day become essential tools for diagnosing allergies, but that day hasn't arrived yet.
For a slightly more reliable allergy test, you can have your vet run a blood test. Blood tests typically cost $200–$300.
To perform this test, your vet will take a blood sample. The sample will go to a lab where a technician will examine it for signs of IgE antibodies, which your dog's immune system produces in response to different allergens.
Like with saliva tests, research has connected blood tests to frequent false positives. However, dogs who receive immunotherapy based on the positive results of blood tests still could see significant improvement in their allergy symptoms.
This test is often more accessible to pet owners because, unlike a skin test, you don't need to see a specialist— your family vet can perform a blood test. Your dog also won't need anesthesia like they would with a skin test, and this is the only allergy test where your dog won't need to stop taking their antihistamines for two weeks beforehand.
The downside, however, is that the false positives can lead to you treating your dog for more allergens than necessary. You'll pay for immunotherapy treatment based on the number of allergens you treat for — each allergen is sold by the vial and you will need to purchase many vials of each allergen throughout the treatment process. So, treating for more allergens than necessary will end up costing you more money over time.
Intradermal Skin Testing
Skin tests are the gold standard of allergy testing. These tests typically cost around $200, and you'll need to find a veterinary dermatology practice to perform the test. Veterinary dermatologists aren't available in all areas and may require a significant drive for some pet owners.
To perform this test, the veterinary dermatologist will give your dog anesthesia. Then, they will shave a patch of your dog's fur and inject specific allergens into your dog's skin. The dermatologist will examine your dog's skin 20 minutes later to see which injections led to allergic reactions.
This test has the most accurate results and can help you and your veterinarian create the most effective plan for your dog's immunotherapy treatment.
Ace the Allergy Test
Finding the right treatment for your dog's allergies can improve their overall wellness and quality of life. We recommend starting with the least invasive and least expensive dog allergy testing by looking for flea allergies and food allergies.
If you rule out fleas and food as possible causes of your dog's symptoms, you can consider environmental allergy testing. But because these tests are expensive and aren't always needed to develop a treatment plan, they're not the right choice for all pets (or pet parents). The only reason to pursue blood testing or intradermal skin testing is if your vet recommends immunotherapy for your dog and you’re willing to undertake the treatment.
Work with your vet throughout your dog allergy testing to develop the most effective plan for your pet's treatment.