Humans aren’t the only species who experience hives, asthma, hay fever, and other allergic reactions. Dogs also commonly experience allergies, and their signs can include chronic itchiness or an acute reaction. A puffy face and itchy hives are telltale signs that your pet has come in contact with an allergen such as bee venom or vaccine serum. These signs can be alarming, but our Village Veterinary Hospital team can easily treat them. Allergic reactions rarely lead to serious and life-threatening complications. Read our guide to learn everything you need to know to identify your pet’s allergy signs and what to do if your four-legged friend has an allergic reaction.
Allergic reactions versus seasonal allergies in dogs
The immune system’s overreaction to normal environmental substances can result in a seasonal allergy or acute allergic reaction, but each allergy type presents a bit differently. A seasonal allergy is a delayed reaction to inhaled substances, such as pollens, molds, or another animal’s dander. An acute (i.e., immediate) allergic reaction is a hypersensitivity response, usually to an insect bite or sting, vaccine, drug, food, or inhaled or contact allergen.
While each is a hypersensitivity reaction, they have various causes and different treatments. A dog with a seasonal allergy is more likely to be allergic to food or fleas, and they are also more likely than the general canine population to develop a sudden, acute reaction because their immune system and body are simply more sensitive than those of most dogs.
Allergic reaction signs in dogs
Allergic reaction signs vary from mild to severe, depending on the specific dog and the allergen amount to which they were exposed. Most reactions typically develop gradually over a few hours and present with the following mild to moderate signs:
- Facial swelling
- Hives (i.e., itchy bumps)
- Vomiting or diarrhea
Anaphylaxis in dogs
Dogs rarely have a severe allergic reaction (i.e., anaphylaxis or anaphylactic shock). Their signs may accompany the ones presented above but usually occur within minutes of allergen exposure. Anaphylactic shock affects the liver, gastrointestinal (GI) tract, and circulatory system, causing blood vessels to dilate and the blood to pool rather than flow normally. Blood vessel dilation and low blood pressure lead to collapse and, in severe cases, death.
Although rare, anaphylaxis most commonly occurs in response to vaccination or drug administration. After your dog receives a vaccination, you should keep a close eye on them, even if they’ve received the vaccine before. Anaphylaxis signs include facial swelling, hives, vomiting, and diarrhea, plus respiratory distress, weakness, and collapse.
What to do if your dog has an allergic reaction
Most gradually developing allergic reactions require same-day veterinary care. If your dog develops swelling or hives over a few hours, seek care with our Village Veterinary Hospital team or with a local emergency facility if the incident occurs when we are closed. Most pets with mild to moderate reactions are stable, so waiting a few hours for care is OK.
If you suspect your canine companion is experiencing anaphylaxis, they need immediate care. Minutes matter with this condition, so the sooner your pet is stabilized, the better. Call while you are en route to alert our team or the emergency hospital that you are on the way.
Allergic reaction treatments for dogs
If your pooch is experiencing a mild to moderate allergic reaction, our Village Veterinary Hospital team will care for your dog as an outpatient. We may provide the following treatments:
- Antiinflammatory injections
- Antihistamine injections
- Oral steroid or antihistamine medications for administration at home
If a dog is experiencing anaphylaxis, they need considerably more support and will likely remain hospitalized overnight once they have been stabilized. Intravenous (IV) fluids and epinephrine help restore blood vessels to their normal size and normalize blood volume, improving circulation and their overall condition. Steroids, antihistamines, and medications to counteract vomiting or diarrhea may also be required.
Prevention and management of allergic reactions in dogs
A severe or anaphylactic reaction is rare, but if your dog experiences one, our Village Veterinary Hospital team will document the episode in your four-legged friend’s medical record. Our team may not administer the offending vaccine or drug in the future or only give your pooch the drug under close supervision while having specific medications on hand to treat a potential anaphylactic reaction immediately. Mild to moderate allergic reactions typically occur once or twice in a dog’s lifetime and don’t require specific prevention or management strategies unless the allergen can be specifically identified.
A few pets experience recurring allergic reactions, typically in addition to exhibiting other chronic allergy signs. To identify offending allergens and develop a plan to prevent or treat the signs, our team may refer your pooch to a veterinary dermatologist who may perform allergy testing and immunotherapy.
You can’t keep your dog in a bubble, so they may experience an allergic reaction at some point in their life. Call our Village Veterinary Hospital team for same-day care if your canine companion exhibits allergic reaction signs. For an after-hours or weekend emergency, reach out to the nearest urgent care or emergency veterinary hospital.