Allergies in Pets

Allergies

Because your pet’s skin or ear infections are an ongoing or recurrent problem, we would like to look into underlying allergies.

Dogs and cats usually manifest their allergies in their skin, ears, eyes, and anal glands (ear infections, skin infections, etc.). The three main causes of allergies are: Flea Allergy, Food Allergy (to ANY protein or carbohydrate source, although usually animal proteins are the culprit), and Environmental Allergy (pollens, mold spores, dust mites, etc.). Allergies change and develop throughout your pet's life, so things that may have been OK in the past can cause allergy symptoms over time. Most pets are allergic to more than one thing, so finding out the cause of the itching can be an involved process. Looking for patterns can help. Does your pet have problems seasonally or year-round? Do you notice the problems getting worse after your pet gets certain treats or after you changed the diet?

Allergies cause inflammation which cause itch and which can cause secondary infections (bacterial and yeast). These infections, in turn, are itchy, so any infection present must be treated as well.

The very first step is to be sure we have eliminated the possibility of flea allergy. For this reason, we will ensure that your pet is on a safe and effective flea control.

To test for food allergies, we adjust their diet. There is no accurate laboratory test to check for food allergies.

Pets can be allergic to any protein source (such as beef, dairy, or chicken) or any carbohydrate (such as wheat or soy)—even wholesome or raw foods—in the same way a person can be allergic to peanuts or fish.

We do a diet trial by eliminating ANY protein or carbohydrate source your pet’s body has been exposed to before and see how the itchiness responds. This can be difficult if your pet has eaten a wide variety of foods in the past - they may have already been exposed to beef, lamb, fish, etc., so we need to choose ingredients your pet has not yet eaten. For this reason, it is best to stick with one food (as long as they are doing well on that food), and keep a log of which foods you have tried in the past, so we know what ingredients might be triggers for the allergy.

If your pet has eaten several different types of food in the past, we may choose a hydrolyzed protein diet, which is a diet prepared so that the protein molecules have been broken down into smaller particles so the immune system does not react to them as allergens.

It is very important that during the diet trial period (8 - 12 weeks on average), you feed ONLY the prescribed diet - no other snack, treats, or flavored chews.

If the itchiness does not improve after a strict diet trial and consistent good flea control, by process of elimination, we determine that the culprit must be environmental allergies or a combination of food and environmental allergies. For environmental allergies, some pets need medications to help keep them comfortable and prevent secondary infections.
 
We can also test for environmental allergies, with the goal of determining what the triggers are and using that information to develop immunotherapy (like the “allergy shots” some humans get). These can be given as drops under the tongue or as injections. Immunotherapy is a long-term approach and can be helpful as part of a multimodal approach to reducing itching, skin and ear infections, and other clinical signs of allergy. It is most effective when started early in life. It can take up to a year to see results, and is effective in 50-75 percent of pets.

Overall, it is important to remember that we cannot cure allergies. We manage them, and often manage them to the point where pets remain comfortable and symptom-free most of the time, but you may see flare ups or patterns that occasionally require an appointment with your veterinarian.

Ilana Halperin, DVM
Updated: 05/2019

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