Allergies occur commonly in pets, whether they pop up suddenly as an acute reaction, or wax and wane with the seasons. Since your pet’s immune system can develop a hypersensitivity to a wide range of allergens, knowing what caused the reaction can be difficult—you know only that they have an allergy. Allergic reactions can also vary in severity, from mild cases that result in no more than a short-lived episode of hives, to severe cases that can lead to anaphylaxis and shock.
Help shield your four-legged friend from the worst allergic reactions by learning allergy causes in pets, signs that may appear, and what to do if your pet develops an allergic reaction.
What are the most common causes of allergic reactions in pets?
Allergies in pets are triggered by a variety of allergens that fall under environmental, chemical, or pharmaceutical categories. Some of the most common allergies that affect pets include:
- Insect bites and stings
- Dust mites
- Household chemicals
- Air fresheners
However, pets can be allergic to any substance, including the dander of other household pets. If your pet frequently develops allergy flares, we recommend allergy testing to determine the triggers.
What are allergic reaction signs in pets?
Allergy signs in pets vary, depending on the allergen that spurred the reaction. The most common manifestations of an allergic reaction include:
- Itching — Itching can be localized or generalized, and normally affects the limbs, face, ears, armpits, and hind end. Itching is typically the main sign in pets with environmental allergies to molds, pollens, and dust. Pets with pollen or grass allergies often break out in an itchy rash on their abdomen and paws after walking through the yard. Flea allergies also cause intense itching that is typically localized to the tail base and the hind end. Itchiness can lead to excessive scratching, licking, and chewing, resulting in skin damage and infection, so treatment of the underlying cause at the first hint of itching is important.
- Facial swelling — Some allergic reactions can result in swelling around the pet’s eyes, ears, and muzzle. A puffy face is easiest to spot in short-haired pets, but a long-haired pet who is scratching and rubbing a swollen face can alert owners to their allergic reaction. Brachycephalic pets with flat faces can experience life-threatening respiratory distress if their face swells too much, so seek immediate treatment if your pug, bulldog, or similar breed develops facial swelling.
- Hives — Hives (i.e., urticaria) manifest as raised bumps on the skin after your pet comes in contact with an allergen. Hives are usually fairly obvious in short-haired pets, but can be difficult to spot in long-haired pets unless they appear in hairless areas such as the abdomen, armpits, and inside the ears. While hives are not life-threatening—unless they spread to the throat and restrict breathing—they can be uncomfortable, so treat your pet for these itchy bumps as soon as possible.
- Gastrointestinal (GI) problems — GI issues, like vomiting and diarrhea, typically result from food sensitivities, but can develop in association with any allergen. A pet’s food allergy is likely caused by a protein in the food, such as chicken, lamb, or dairy. Grains rarely cause allergies in pets, despite the common misconception. Pets with a food allergy can also be itchy, particularly in their ears and paws, resulting in chronic ear infections and excessive paw-licking.
- Anaphylaxis — Anaphylaxis is the most severe allergic reaction, and can cause the body to go into shock. Typically, anaphylactic reactions worsen with each allergen exposure, and signs develop only minutes after contact with the allergen. For example, your pet’s reaction to their first bee sting may be localized, but the next sting can result in systemic anaphylaxis. Signs that indicate your pet is having an anaphylactic reaction include typical allergic reaction signs of itching, facial swelling, and hives, but can also include difficulty breathing, excessive drooling, severe vomiting, diarrhea, and lethargy. Left untreated, anaphylaxis can progress to collapse, convulsions, and potentially death.
How is a pet’s allergic reaction treated?
Most allergic reactions are treated the same way, regardless of the triggering allergen, but will differ based on severity. Treatment can include an antihistamine and a corticosteroid injection to squelch the overactive immune system’s inflammatory response. Pets with severe cases may require oxygen supplementation, intravenous fluids, and emergency drugs such as atropine and epinephrine.
Pets with chronic seasonal allergies can benefit from a variety of management techniques and products, including:
- Medicated shampoo
- Regular ear cleanings
- Allergy medications (e.g., Apoquel, Cytopoint)
- Skin supplements
- Prescription diets
What to do at home if your pet has an allergic reaction
If your pet has an acute allergic reaction—to a bee sting, for example—follow these at-home steps:
- Remove the allergen — If your pet has been stung, remove the stinger. If they came in contact with a chemical, wash their skin thoroughly with soap and water. Remove the allergen in any way possible to minimize your pet’s reaction.
- Keep your pet calm — An allergic reaction can cause a great deal of discomfort and make your pet anxious and agitated, which can worsen breathing issues. Keep your pet calm, and move quickly to treat their reaction.
- Monitor your pet’s breathing — If your pet develops breathing difficulties at any point, seek emergency veterinary care.
- Consult your veterinarian about administering medication — Antihistamines may help treat your pet’s allergic reaction, but always contact your veterinarian before giving medications.
Allergic reactions in pets can cause serious, life-threatening problems. If you suspect your four-legged friend is having an allergic reaction, contact our Creature Comforts Veterinary Service team immediately.