Allergies are one of the most common health problems for pets.

Signs include scratching, ear infections, licking paws, over-grooming, hair loss, and itchy, swollen skin. Some animals can have respiratory/ocular signs as well - sneezing, runny nose, and red, watery eyes. Just like in people, allergies are a result of the body's immune system overreacting and releasing inflammatory cells and substances such as histamines.

Key Points

  • Allergies can't be cured, just managed. They are life-long chronic problems and can make pets very miserable if not controlled.
  • The best way to treat effectively is to get an accurate diagnosis by finding out what your pet is allergic to. In mild allergies, sometimes just controlling the signs is a good way to start treatment, but keep in mind that further testing may be recommended if medications are not effective.
  • Although there are different types of allergies, pets can have allergies to multiple things (ex: flea allergy and food allergy) making it difficult to diagnose the cause.
  • Pets with allergies can be very miserable! They are licking and chewing because of this discomfort, so deterrent sprays and Elizabethan collars are NOT an effective stand-alone treatment. Think about how you would feel if you were so itchy and couldn't scratch! It is important to treat the itchiness and not just prohibit the pet from scratching.


Atopy - environmental allergies

  • Atopy is a very common type of allergy that we see in pets. Just like us, pets can be allergic to pollens, grasses, and molds that are more common during certain seasons of the year. They can also be allergic to dust mites, mildew, and mold that can be inside homes all year round. These kinds of allergens usually produce severe itching in pets, which is usually concentrated in the ears, feet, groin, and armpits since these are the areas that come in contact with the allergens, though it can be spread across the entire body. Often pets can get secondary bacterial or fungal skin infections that must be treated. Atopy does not generally start until they have gone through a couple of seasons of whatever they are allergic to, so puppies are usually not affected.
  • Testing: Atopy testing is generally a blood test or intradermal skin test (injections into the top layer of skin) to determine what environmental factors the pet is allergic to. Allergy tests are specific to the area the pet lives in, and ideally testing is done after the pet has lived in an area for 2 years. Allergy testing must be repeated every 2-3 years since allergies can change over time.
  • Treatment:
    • Specific treatment from allergy testing is hyposensitization. This involves giving or injecting small amounts of what they are allergic to regularly (usually weekly) so that the immune system gets used to it and no longer reacts to that substance over time. It can take 6 months - 1 year to see results. Studies show that up to 80% of animals respond favorably to hyposensitization treatment.
    • Cytopoint is a new injection that targets atopy in dogs. It is an injection that binds the cytokines responsible for itching in atopic dermatitis. It can last 4-8 weeks and after continued use, can last longer. It is a great new option to help dogs feel better quick. Results are usually seen in 4 days, but some animals have less itching in as little as 12 hours. Over time, use of Cytopoint can help the skin heal, reducing allergic reactions.

Food allergies

Diet can be a complicated factor in pet allergies. Most animals are not born with allergies to food; their immune systems develop an allergic response over time to some part of their diet, often one of the animal proteins. Food allergies can start as early as 6 months of age. Food allergies can present as itching, digestive disorders, and skin and ear infections.

Testing/Treatment: In the case of food allergies, testing involves diet trials with hypoallergenic foods. If the food works to control the symptoms, the pet is kept on these foods as a treatment. A diet trial takes 8-10 weeks since allergic effects of the food can stay in the system for that long. During this time, your pet cannot get anything else to eat. This includes treats, vitamins and supplements, and they need to be on special heartworm prevention that is hypoallergenic. Even eating crumbs off the floor can interfere with a diet trial, which can make it very challenging. After a successful diet trial, possible allergens can be re-introduced to determine exactly what the pet reacts to.

Flea allergies

Flea allergy is common but luckily we have lots of great medications to control flea infestations if they are used properly. Some animals can have multiple fleas with minimal discomfort, but flea allergic animals have severe reactions to only a few flea bites. Affected animals can itch severely from a single bite for over five days! Flea allergic animals and all other pets in the household should be on prescription flea prevention year round. Environmental treatment (house and yard) is also important for flea allergy patients. Flea allergy reactions are often seen around the tail and tailhead (on the back just in front of the tail) since fleas prefer these areas that are difficult for the animal to reach. Cats are good groomers and often groom off the adult fleas that they are reacting to, so not seeing fleas is not a guarantee that they are not the issue.

Contact allergies

These are the least common type of allergy in animals. They happen when an animal's skin comes in contact with the material he's allergic to--if he rubs his face against a wool blanket, for example, and he's allergic to wool. The chemicals in flea collars can cause this problem as well. The skin at the point of contact will be irritated--it may itch, become thickened or discolored, have a strong odor, and/or lose hair due to constant biting or scratching. Contact allergies are generally not a hard problem to solve--they're usually confined to a specific area of an animal's body, and the allergen shouldn't take too much work to discover. You can try removing different materials that your pet touches until you find the one that irritates his skin.


Sometimes it is difficult to determine exactly what is causing your pet's reaction, or removing the allergen is not possible, which makes management challenging. You and your veterinarian have to work together to determine the best treatment, or combination of treatments, for your pet's allergy. Your veterinarian may suggest one or more of the following things:

  • Testing - as previously mentioned, blood tests for allergies or intradermal allergy tests can help direct hyposensitization treatment. For secondary infections, skin tests to include skin scrapes, cytology, ear swabs, and cultures can help rule out other problems and direct treatment of bacterial or fungal skin infections.
  • Antihistamines-These drugs, much like the allergy medication people take, work to block the chemicals released by the immune system, called histamines. They can help with mild itching/inflammation and are relatively safe to use. Different antihistamines work on different dogs so sometimes you have to try different ones to find the antihistamine that works best for your pet.
  • Steroids--These drugs work to suppress the immune system and make the allergic reaction less severe. Steroid treatment can help your pet even if you can't determine what he's allergic to or how he's being exposed. Steroids affect multiple organs in the body and can have significant side effects especially if used long-term. Steroid use can cause weight gain, increased thirst and urination, and increased aggression and other behavioral changes.
  • Apoquel is a pill that is fast and effective at stopping itching. It targets specific cytokines that cause itch and inflammation in allergic skin disease, relieving symptoms with minimal impact on the immune system. It is meant to be used short term but can be used longer in severe cases. It is a new type of drug that does not interact with other medications and can start working within 4 hours.
  • Fatty acid supplements - fatty acids are substances which can help decrease inflammation in the skin. They also help your pet to have a shiny, healthy hair coat. Your veterinarian may recommend your pet stay on fatty acids as part of their allergy treatment. They may not fix the problem, but can often decrease the amount of other treatments your pet requires. Please keep in mind that it can take up to 6 weeks for fatty acids to start having an effect. They are dispensed in a liquid for or in a capsule that can be squeezed over your pet's food.  We recommend VRS Omega Benefits.  
  • Dietary Therapy - besides foods for diet trial in food allergies, there are foods with high concentrations of fatty acids and other additives to decrease inflammation. Sensitive skin and stomach foods are commonly available over the counter and can be a good adjunctive treatment for allergies (we like Pro Plan). There are also prescription diets which can provide more targeted allergy treatment, such as Derm Defense by Science Diet.
  • Topical Treatment - shampoos, sprays, and other topicals can be a valuable addition to allergy treatment, although they are rarely used as sole therapy. Your veterinarian will decide on the best topical based on your pet's signs and secondary infections. Another type of topical treatment for dogs that lick their feet a lot is wiping feet either with an antibacterial solution of mild soap and water. Wiping feet after coming in from outside can remove pollens and allergens.

Whatever treatment decision you and your veterinarian come to, rest assured that the patience and determination it can take to treat allergies is well worth it. Though it may take some time and effort, you can help your itchy, grouchy pet feel comfortable again.