Tell All on Allergies in Dogs


Q: Can you tell me about allergies in dogs. We just moved from the Midwest to Florida and our dog now has an allergy, itching a lot, an awful lot. A.C., Lake Magdalene, FL

A: Allergies in dogs – that’s as broad a topic as allergies in humans.

An allergy is a state of over-reactivity or hypersensitivity of the immune system to a particular substance called an allergen. Most allergens are proteins from plants, insects, animals, or foods.

In the dog, the most common symptom associated with allergies is itching of the skin, either localized (in one area) or generalized (all over the body). In some mor unusual cases, the symptoms involve the respiratory system, with coughing, sneezing, and/or wheezing similar to humans. Sometimes, there may be runny discharge from the eyes or nose. In other cases, the allergic symptoms affect the digestive system resulting in vomiting and/or diarrhea.

The most common allergy in dogs is actually caused by flea bites, or even a single bite, called flea allergy dermatitis. Since you had no issue in the Midwest, and Florida offers a festival for fleas all the time, I suggest you consider this possibility. Flea allergy dermatitis can typically be prevented with appropriate veterinary recommended flea protection.

The next most common allergy on the hit list is the most common cause of sneezing and wheezing in people, called inhalant allergy or atopy. Dogs are allergic to the same stuff we are, such as grasses, pollens, ragweed, molds and even house dust mites. Many of these issues occur seasonally.  In most dogs, inhalant allergy manifests with itchy skin (pruritus). The dog may also rub her face, lick the bottoms of their paws and scratch the underarms. If the signs are seasonal, or as described here, inhalant allergies are likely the culprit.

Special shampoos can help to sooth itchy and inflamed skin but it’s not an effective preventative. Closing windows and vacuuming with a HEPA filter cleaner may help some. Certain antihistamines can be used but never go to your own medicine cabinet as some human allergy or cold products may be dangerous for dogs. Steroid treatment can be temporarily used to help dogs.

Newer and more efficient alternatives exist to block specific chemical signals associated with itch in dogs. These drugs include a daily oral medication, called Apoquel, or a long-acting injection, called Cytopoint. Your veterinarian can help you determine whether these medications may be appropriate.

A true food allergy or food hypersensitivity can develop to almost any protein or carbohydrate component of food. It most commonly develops in response to protein and more rarely other products in food. Clinical signs that may occur can be itching, digestive disorders, and/or respiratory distress. Similar signs may occur if a pet doesn’t have a true allergy but instead have what’s referred to as an intolerance to an ingredient or ingredients in a food.

Treatments discussed above for inhalant allergies are not likely to be choices for solving food allergies. It’s important to attempt to confirm that the current diet is at issue. A food diet elimination trial is an efficient way to do it, offering a novel protein diet for eight to 12 weeks. Sadly, this only means a diet and treats approved by your veterinarian. Any variation will mess up the trial, including unapproved table food.

Contact allergy is the least common type of allergy in dogs, which results from direct contact to allergens, such as pyrethrins found in flea collars, pesticides used on the lawn, or materials such as wool or synthetics used in carpets or bedding, etc. It’s very rare but it is possible for a dog to be allergic to cats or even other dogs.

Caution: The symptoms of allergies can be confused with other disorders, or occur concurrently with them. Therefore, do not attempt to diagnose your dog without veterinary professional assistance.