Allergies in Dogs: Symptoms, Triggers & Treatment

3 min read
Jul 12, 2023

Does your dog bite or lick their paws? Do they obsessively scratch their skin? Do you notice them itching only at certain times of the year? Does your dog suffer from recurring ear infections?

If you answered yes to any of these questions, your dog may be suffering from allergies. But you don’t have to stress. Once you understand what can cause an allergic reaction and how to treat it, your dog could get back to living a happy and healthy life.

What Is an Allergic Reaction in Dogs?

An allergic reaction is the result of your dog’s immune system responding to a particular foreign substance or allergen. Allergens are generally harmless substances. However, a hypersensitive immune system can identify these foreign substances as invaders and overreact in an attempt to protect the body.1

What Are Common Signs of Allergies in Dogs?

Allergic reactions in dogs can take different forms and affect your dog in various ways. Some of the more common types of reactions include the following.

Skin reactions

Skin allergies, also known as atopic dermatitis, can be some of the most common allergies seen in dogs. The typical symptom is itchy skin. But your dog may also show signs of swelling and inflammation of the skin, red bumps, shedding, or mange.

Dogs with skin allergies may scratch and lick at affected areas repeatedly until they get “hot spots.” These are patches of skin that are moist, warm to the touch, and cause your dog discomfort. This can become a vicious cycle, where the skin becomes irritated, your dog scratches and licks — further irritating it — and the cycle repeats itself.

If you notice these hot spots, they should be treated as soon as possible since open skin wounds can become infected.

Ear, nose, throat, and respiratory symptoms

Dogs may also suffer from reactions to inhaled particles, including symptoms like red, itchy, puffy, or watery eyes, wheezing, and coughing. They may also show signs of nasal irritation, like runny nose, sneezing, or reverse sneezing.

Digestive symptoms

Another possible type of allergic reaction for dogs may be gastrointestinal problems, such as diarrhea or vomiting. If your dog’s anal glands are irritated due to allergies, they may also lick their butt or scoot it on the ground.

Anaphylactic reaction

This is the least common type of allergic reaction, but it's potentially the most severe. These types of allergic reactions tend to come from bee or wasp stings, or an adverse reaction to a new medication or vaccine. Symptoms may include facial swelling, sudden vomiting or diarrhea, difficulty breathing, collapse, or even death.1

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What Are Common Allergy Triggers in Dogs?

Dog allergies can often be triggered by substances they inhale, ingest, or get on their fur and skin. The substances that trigger an allergic reaction are usually referred to as allergens. While there are many different types of allergens, some of the most common tend to be environmental allergens and food allergens.

Environmental allergens

Environmental allergens can come from both natural and artificial sources, and they can trigger many of the allergic reactions described above. Some of the most common types of environmental allergens for dogs include:1

  • Seasonal allergens: These are naturally occurring allergens — like pollen, mold, grass, dirt, and plants — that tend to grow or appear at certain times of the year.
  • Flea and parasite allergens: While flea bites and other parasites can be annoying by themselves, another common cause of skin allergies is flea allergy dermatitis — an allergic reaction to the saliva spread by flea bites or dust mites.2
  • Other animals: Your dog can have an allergic reaction to animal dander, fur, or feathers.
  • Chemicals: In addition to cigar or cigarette smoke, dogs may be allergic to cleaning products or strong soaps, perfumes, and shampoos. Your dog may also have a reaction to the plastics found in some food bowls and water dishes.
  • Pest control products: This may include bug sprays and chemical traps. If you hire an exterminator, let them know you have a dog so they can use a pet-safe products.

Food allergens

Another possibility can be a food allergy, which may be caused by one or more ingredients in your dog’s food. Some common ingredients that may trigger an allergic response in your dog include chicken, beef, lamb, or even wheat.

Also, food allergies don’t always occur right away. Your dog may develop an allergy to a type of food, even after they’ve eaten it for a number of years.

Food allergies vs. food sensitivity

If your dog doesn’t tolerate some store-bought food well, it may be food sensitivity rather than a food allergy. While a food allergy is triggered by the immune system, a food sensitivity is triggered by the digestive system.

Signs of a food sensitivity may include gastrointestinal problems, like diarrhea or vomiting. If your dog isn’t getting enough nutrition because their food doesn’t agree with them, it can also contribute to a poor coat, itchy skin, or chronic infections of the ears or feet.

How To Treat Allergies in Dogs

If your dog is suffering from allergies, there are different treatment options available based on whether the allergen is environmental or food-related. Depending on your chosen method — medication, immunotherapy, or diet — dog allergy treatment costs can vary.

Medications for allergies in dogs

If you suspect an environmental allergen is contributing to your dog’s allergies, try to eliminate it if you can, or switch to a pet-friendly product. If it isn’t possible to keep your dog away from an environmental allergen, your veterinarian may be able to recommend one of these over-the-counter treatments to help make your dog’s life a little easier.

  • Antihistamines: Certain medications, like Benadryl for dogs, can block the body’s immune response to prevent allergic reactions and anaphylaxis.
  • Steroids: Your vet may prescribe topical hydrocortisone for use on your dog’s skin to relieve hot spots, itching, and other skin problems.

When over-the-counter medications aren’t strong enough, your vet may prescribe an anti-itch pill, like Apoquel, or an anti-itch allergy shot, like Cytopoint. These dog allergy treatment costs can vary depending on where you live, the size of your dog, and how often they need the medication — and could be a few hundred dollars per year.


If your dog has severe allergies or doesn’t respond well to medication your vet may recommend immunotherapy. This treatment introduces small amounts of the allergen to your dog’s body and gradually increases the dose over time, allowing them to build up a resistance.3

To help narrow down a potential cause, your vet may recommend a skin test or blood test that can show what substances, or types of substances, your dog may be reacting to. Dog allergy testing costs vary based on where you live and how many tests are needed, but it may cost around $200 or more.4

Once the allergens are identified, your vet may use under-the-skin injections or under-the-tongue drops to introduce the allergen. It can take up to a year to determine if the treatment is effective, so your vet will probably continue to recommend medication or other treatments.3

Elimination diets

If you’re concerned that your dog may be allergic to an ingredient in their food, talk to your vet. Depending on the severity of your dog’s response, the vet may recommend an elimination diet.

With an elimination diet, you may need to feed your dog a prescription diet for a few months. Once their allergy symptoms have cleared up, you can reintroduce foods back into your dog’s diet to help determine which ones were causing the allergic reaction.

From there, your vet may be able to recommend a different brand that provides them with the right balance of nutrients while eliminating ingredients that may be causing an allergic reaction.

Does Your Dog Have Allergies? Consider Dog Insurance

If you suspect your dog has an allergy, it’s recommended that you get a proper diagnosis by scheduling a vet visit. A complete evaluation and medical history review can help target the root cause quickly and effectively.

While allergies can be treated, they can’t currently be cured. This can lead to long-term costs for medications or immunotherapy. Getting a dog insurance policy can help make these more affordable, so you can focus more on giving belly rubs and less on veterinary bills.

Take Millie, a young pup from California, for example. Millie’s owners started noticing her itching after playing outside. One vet visit later, she was diagnosed with environmental allergies. The visit and initial treatment cost almost $1,300, but her pet parents were reimbursed for the entire bill thanks to their pet insurance policy. 

A MetLife Pet policy also helps senior Nevadan dog, Tank, with his yearly allergy exams and treatments that cost around $500. For his third-year visit, Tank’s parents were reimbursed over $460 because of their dog insurance policy.5

Ready to explore coverage options with MetLife Pet Insurance? Learn more about the cost of pet insurance, or get your free personalized quote today.

Help Keep Your Dog Healthy and Happy


** As with any insurance policy, coverage may vary. Review our coverage and exclusions.

1 “Allergies in Dogs: Common Allergens & Treatment,” Bond Vet

2 “Flea Allergy Dermatitis in Dogs,” VCA Animal Hospitals

3 “Immunotherapy (Allergy Shots) for Dogs,” Veterinary Medicine at Illinois

4 “How Much Does Dog Allergy Testing Cost?,” Pet Keen

5 All claims paid amounts are based on MetLife internal claims data from October 2022. Story altered for illustrative purposes.

Coverage issued by Metropolitan General Insurance Company (“MetGen”), a Rhode Island insurance company, headquartered at 700 Quaker Lane, Warwick, RI 02886, and Independence American Insurance Company (“IAIC”), a Delaware insurance company, headquartered at 11333 N Scottsdale Rd, Ste 160, Scottsdale, AZ 85454. Coverage subject to restrictions, exclusions and limitations and application is subject to underwriting. See policy or contact MetLife Pet Insurance Solutions LLC (“MetLife Pet”) for details. MetLife Pet is the policy administrator. It may operate under an alternate or fictitious name in certain jurisdictions, including MetLife Pet Insurance Services LLC (New York and Minnesota) and MetLife Pet Insurance Solutions Agency LLC (Illinois).

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