Why Does My Dog Have Hives?

What are hives?

Hives are skin rashes or welts that are red, swollen, and usually itchy. The red skin welts can develop on any part of the body, including the dog’s face, throat, lips, and ears. Most of these reactions are localized and often resolve on their own.

Hives in dogs are not as easy to detect as they are on the skin of people because of the dog’s dense hair coat. You may see the rashes on areas of the dog’s body with less hair but other than that, all you may notice are several small raised tufts of hair that indicate the presence of the raised welts. The skin welts may be itchy or may not bother your pet at all.

Causes of Hives in Dogs

Hives develop when there is a localized release of histamine in the skin. This can cause the dilation of blood vessels in the area. The local inflammation eventually gives rise to small reddish welts and bumps that are collectively called hives. Small hives can merge and form larger skin welts and bumps.

There are many known triggers of hives in dogs. Any allergen that your pet is hypersensitive to can cause hives. Some of the most common include:

• Bee or wasp sting and other types of insect stings
• Spider bites
• Food allergies
• Vaccines
• Environmental allergens - pollen, molds, dust, etc.
• A chemical reaction to insecticides
• Shampoos
• Medications
• Supplements
• Plants - such as Poison Ivy or Stinging Nettle
• Genetic abnormalities

Some factors that can intensify the rash include exposure to sunlight, friction, stress, heat, and exercise.

In a study about urticaria in dogs, insects, food, and drugs were the most frequently detected triggers. Identifying the trigger factor of your pet’s hives can help you prepare for possible episodes in the future. Hives may return rapidly if your dog continues to be exposed to the trigger(s).

Symptoms of Hives in Dogs

• Areas of redness and swelling develop on the dog’s face, legs, and abdomen.
• Swelling around the dog’s muzzle can lead to drooling
• Excessive scratching
• The dog’s eyes appear to be closed as a result of the swelling around them.
• The hives often appear as raised circular bumps on the skin surface.

There are instances when the reaction can worsen if appropriate treatment is not given. This could be life-threatening as the swelling could cause the dog’s throat to close. Affected dogs can also suffer from intense itching, causing them to scratch excessively, which can also make the reaction more severe.

Are hives harmful to my dog?

If skin swelling is caused by bee or wasp stings, there may be a dramatic swelling around the dog’s face and lips. There is a possibility that the swelling could progress to the dog’s throat. This serious reaction is called anaphylaxis, and when this happens it could compromise the dog’s respiratory passages, making it difficult for the dog to breathe. This is one of the reasons why an anaphylactic reaction should be treated as a medical emergency. Prompt veterinary attention should be sought.

Fortunately, this life-threatening reaction is very rare. Most cases of hives in dogs are self-limiting and don’t pose a significant health threat to your pet.

How to Treat Your Dog’s Hives

Depending on the severity of the allergic reaction, your vet may prescribe antihistamines or rapid-acting corticosteroids. When administered by injection, these medications could produce dramatic improvements within a few minutes.

Can my dog’s hives be treated at home?

Once the dog’s exposure to the allergen has been removed or minimized, hives tend to resolve on their own. But it can usually take between 24-72 hours to clear up. To prevent excessive scratching which can make the skin raw, apply ice or a cold towel on your pet’s skin. The cold can help soothe and alleviate the itching.

Bathing your pet in cool water is also another way to soothe his skin and relieve the itching and inflammation. Irritants and allergens on your pet’s skin can also be washed off during bathing.

There are also natural remedies for skin itching that you can try at home. These include chamomile and herbal tea soaks, apple cider vinegar water spray, an oatmeal bath or paste, coconut oil, and plain yogurt.

You can also ask your vet about home remedies for your pet. These may include topical products or prescription medications depending on the cause and nature of your pet’s allergic reaction.

While most cases of hives can be treated at home, contacting your vet is recommended because of the possibility that it can lead to more serious reactions as the allergy spreads to other parts of the body.

If your pet has recently received a vaccine or medication and has developed hives, contact your vet immediately so you can be instructed on what to do.

Ways to Prevent Hives in Dogs

Avoid exposing your dog to the allergen culprit. This is the best way to prevent hives in dogs. But this is easier said than done. Allergens abound in your dog’s immediate environment or they could be in your pet’s food. There is a need to undertake measures to identify the allergen culprit so you can minimize or altogether prevent your pet from exposure.

If your dog reacted to a particular vaccine in the past, your vet may give your pet a shot 10-14 minutes before the administration of the vaccine. Your vet may also deem it necessary to modify future vaccination protocols for your pet to minimize adverse reactions.

Read more:

Why is my dog itchy?

Allergic Ear Infections (Allergic Otitis) in Dogs

Common Myths About Allergies in Dogs

Need to speak with a veterinarian regarding your dog’s hives or another condition?

Click here to schedule a video consult to speak to one of our vets. You can also download the FirstVet app from the Apple App Store and Google Play Stores.