Puppy itching
There are few things worse than an itchy dog or cat — so uncomfortable, constantly licking and chewing at his paws and flanks, and rubbing his face on the sofa or carpet to try to relieve the discomfort. Just miserable.

Allergies are one of the more common problems I see in pets, and according to data from pet health insurance companies, it’s the No. 1 medical condition that dog owners seek treatment for. My own Gracie, a Lab-Pit Bull mix, is one of the sufferers.

The incidence of pets afflicted with allergies varies throughout the country and is often related to climate or season. Common causes of allergic reactions are flea bites; pollens, molds, grasses, trees, weeds, dust and dust mites; and certain food ingredients.

Identifying Allergies

Some pets are extremely allergic to flea saliva and have a condition called flea allergy dermatitis (FAD). When fleas bite these pets, saliva gets into the animal’s bloodstream, causing an allergic reaction. The bite of a single flea can send some sensitive pets into a scratching, licking or chewing frenzy.

Dogs with FAD are usually itchy on the back half or third of the body. Cats often have crusty areas around the head and neck, but the back half of the body can also be itchy.

Dust, mold and pollen are environmental allergens. They typically occur only at certain times of the year, depending on what’s in bloom or particular climate conditions, and they often cause seasonal itching. Your veterinarian may refer to this type of allergy as an inhalant allergy or atopic dermatitis.

Finally, some pets develop allergies to certain proteins such as beef, chicken or soy. Pets with food allergies typically experience itching all year long, and some may have gastrointestinal signs.

Diagnose the Itch

Sometimes veterinarians know from an examination or a pet’s medical history what’s causing the itchiness. We see flea dirt, for instance, or the scratching is seasonal, suggesting that environmental allergens may be the problem.

When we don’t have any clues, though, diagnosing allergies is a process of elimination. We make sure the pet is on a good flea-control program; we do skin scrapings to check for other possible parasites. We also look for bacterial or yeast infections, which can contribute to itchiness in dogs and cats with allergies; and we may even start the pet on an elimination diet to rule out food allergies.

When we suspect a food allergy, we may recommend feeding a food that contains only ingredients the pet has never eaten before. This elimination diet can help determine if a particular ingredient is causing a pet’s itching and scratching. If the signs go away after 12 weeks of feeding only the hypoallergenic diet (no treats or other foods that might contain allergenic substances), we start to add ingredients back into the diet one by one until it’s clear which one is causing the problem. Then it’s just a matter of finding a food for your pet that doesn’t contain the dietary troublemaker.

If the itching stops, we know we’re doing something right, but we still have to figure out what’s actually causing the problem. In the case of fleas, your pet may need a different flea preventive more suited to his lifestyle. For instance, water-loving dogs who spend every day in the pool may have poor results with topical treatments, even if the substance is water resistant. In those cases, we may suggest an oral product that works more rapidly. If you are applying or giving the product only when you see fleas, we’ll probably advise that you use it more regularly, even if you don’t see evidence of fleas.

Whatever you’re using, make sure it’s appropriate for your pet. Many products that are safe for dogs aren’t safe at all for cats. Especially if you have both a dog and a cat, read the label carefully before you give anything to make sure you haven’t accidentally picked up the wrong product.

Treating the Problem

If the itching doesn’t disappear with a good flea-control program and a hypoallergenic diet, that’s a clue that we’re dealing with an environmental allergy. Those substances can’t be controlled with human intervention short of moving your pet to a different locale or encasing him in a plastic bubble.

For mild itchiness caused by environmental allergies, we may try antihistamines (without decongestant) first. Frequent bathing with soothing shampoos may help some pets. For more severe cases, veterinarians may recommend other medications, such as steroids, to help relieve the itch. Always consult with your veterinarian before giving your pet over-the-counter medication, though.

Dogs and cats can also be tested to determine exactly what substances set them off. A veterinary dermatologist can then create an allergy shot to try to reduce the pet’s reaction to those substances. Allergy shots can help relieve itchiness in 70 to 75 percent of pets treated, but we may need to adjust the treatment with seasonal or climatic changes. Pets with food allergies will need to remain on a hypoallergenic diet for the rest of their lives.