Dog Allergies: Everything You Need To Know

You or someone you know has suffered from allergies at least once. Whether they carry an epi-pen or just get a slight sniffle in springtime, allergies are incredibly common. But did you know that your dog can have allergies too?

There are many different types of allergies for dogs (as there are with humans), all of which can cause various reactions. Some dogs may develop a slight sniffle or itchiness, whereas others can experience anaphylaxis and die. Regardless of their reaction, allergies make dogs uncomfortable. Most allergies fall into one of three categories: Environmental, food, and flea allergy dermatitis. But what are the differences between these three? 

Environmental Allergies

Environmental allergies in dogs are often caused by pollens, molds, and grasses and can cause reactions like rashes, sneezing, itching, excessive licking, swelling, etc. Because of the changing pollen levels throughout the year, your dog may only struggle seasonally. If you notice rashes around your dog’s paws, ears, and stomach, it might be a sign that they have environmental allergies.

Food Allergies

Like humans, dogs can have allergic reactions to certain foods. Though it’s unlikely it’s a true food allergy that’s upsetting your dog, but rather, a food sensitivity. An allergic reaction to food can cause an immediate reaction such as swelling, vomiting, hives or rash, diarrhea, or anaphylaxis. Sensitivities cause similar (but less severe) reactions that take longer to appear than an allergic reaction. Common signs of food sensitivity include diarrhea, vomiting, yeast infection, and an itchy coat. If you suspect your dog has an allergy or sensitivity to their food, contact your vet, and they can help you devise a plan to help Fido. Luckily, many hypoallergenic dog food brands may benefit dogs with allergies or sensitivities, so your dog can live a happy, healthy life even with allergies.

Flea Allergy Dermatitis

Some dogs are allergic to flea saliva, which can cause an itchy, scabbing, or reddened coat – particularly at the base of their tail. This phenomenon is called Flea Allergy Dermatitis (FAD) and can be incredibly uncomfortable for dogs, especially if left untreated. Dogs can develop secondary skin infections from scratching or biting, thus creating a vicious cycle of discomfort. The best way to prevent FAD is to keep your dog as far away from fleas as possible. Be sure to regularly check your dog’s skin and clean areas that are at risk for housing fleas. If your dog already has FAD, contact your veterinarian. They may recommend topical medications, flea sprays, or more than one product that can kill fleas.

One of the best ways to prevent your dog from an allergic reaction is to keep them away form the allergen, but this isn’t always possible. Many owners don’t even know their dog has an allergy or sensitivity. If you’re curious as to what may be upsetting your dog, there are ways to find out the cause of your dog’s discomfort, the most common being allergy testing.

Allergy Testing

To test what your dog might be allergic to, you’ll need a veterinarian to perform a radioallergosorbent test, also known as a RAST test. These are most commonly performed when a dog experiences atopy, a skin reaction to inhaled allergens or irritants. Your vet will draw a sample of your dog’s blood and send it to a reference lab, where you can learn what irritants may be causing your dog’s skin issues. Though, RAST testing is more likely to result in a false positive than intradermal skin testing.

Intradermal skin testing is the more accurate but invasive way to test your dog’s allergies. It can only be performed by a veterinary dermatologist, which may not be available to you depending on where you and your dog are located. Plus, veterinary dermatologist bills can be expensive. The process involves shaving a portion of your dog’s fur, pricking the skin with different allergens, and then waiting to see if your dog has an atopic reaction. Your dog’s dermatologist will then recommend a plan based on the severity of your dog’s response to prevent reactions from occurring.


Overall, allergies can be a struggle for pets, but there are ways to prevent them from suffering. If you have any concerns about your dog’s health or suspect they have allergies, take advantage of modern veterinary medicine and contact your vet. Best of luck to you and your furry friend!

Abigail Kurten
Author: Abigail Kurten

Hi! My name's Abigail, and I intern as a Content Writer for I have one dog, a chocolate lab named Riley who's the best! My favorite breed of dog is a Bulldog or Saint Bernard, though.

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