Allergies in Pets: How They Manifest and How to Treat Them
Like humans, dogs and cats can be sensitive to various kinds of allergens—either in the air, in their food, or on their bodies. The most common symptoms which may indicate an allergic reaction in your dog or cat include excessive itching, biting, or licking of their body. In cats, allergies will sometimes lead to respiratory issues. When seeing a pet who is showing symptoms of an allergic reaction, we first try and determine the source or cause of the allergic reaction. There are three different sources of allergens that can harm our pets: allergens in the air, in food, and in fleas. In general, fleas are the easiest of these allergens to treat; some dogs and cats have what is called flea allergic dermatitis—this means that while they will get a small localized reaction from where a flea bites them, they will also have a larger systemic reaction which causes them to itch all over their bodies. In instances such as these, we simply need to get the dog or cat started on an adequate flea control medicine and the problem should dissipate. For ingested and environmental (also called atopic) allergies however, determining the source of and proper treatment for the allergic reaction can be a much more difficult proposition.
Statistically speaking, environmental allergies are much more common than food allergies in animals. However, we almost always target food allergies first for two reasons. First, although food allergies are less common, they are much easier to control for. If your dog is allergic to chicken, you can easily remove that from their diet; if, however, your dog is allergic to oak pollen, you aren’t going to have much luck getting pollen out of the air. The other reason for looking at food allergies first has to do with something called the “allergy threshold”. One way to understand the allergy threshold is to think of a tea kettle being heated to make boiling water: over time, as more and more heat gets added, the water in a tea kettle will get closer and closer to boiling; however, until the water is at a full boil, the whistle on the pot won’t sound. The point at which the kettle starts to whistle is analogous to an animal reaching its allergy threshold. Allergies are additive, meaning that each new allergen a pet is exposed to places additional stress on their body’s immune system. Just as a kettle won't whistle until the water reaches 212 degrees, a pet will not become symptomatic until the "accumulated" allergens in their body exceed a certain threshold. What this means is that you and your veterinarian may be able to alleviate your pet’s allergy symptoms by simply removing a small portion of the total allergens to which they are exposed. For example, if 80% of a dog’s allergen exposure comes from pollen in the air around him (something we can’t control for) while only 20% comes from the food he’s eating, removing that small amount of food allergens may be enough to slip the pet beneath her allergy threshold and relieve her allergic symptoms. So, even though food allergies statistically make up a much smaller proportion of pet allergens than environmental allergies, it is still prudent to go after them first in the hopes that, by eliminating the portion of allergens which are easily controlled, we may be able to get a pet beneath her allergy threshold.
If we’ve changed a dog or cat’s diet and not seen an improvement in their symptoms, we often then try treating the allergies symptomatically by administering a drug or supplement that decreases or minimizes their immune response to allergens. This is akin to a human taking an antihistamine when they begin to feel their allergies acting up. Dogs and cats can also be placed on antihistamines, and there are also nutritional supplements like fish oil, a natural anti-inflammatory called duralactin, and products such as canine dermal support which may decrease itching and scratching in your pet. You should always consult your veterinarian before beginning any of these over-the-counter treatments.
For more acute cases that do not respond to the above treatments, we may prescribe a corticosteroid. These medications act as powerful anti-inflammatories but come with the possibility of severe side effects, especially when administered long term. For this reason, steroids are not a first line of defense against allergies and are generally not recommended to be given over long periods of time. When a dog or cat has reached the point where we want to consider using steroids, it is often prudent to also consider allergy testing.
Allergy Testing and Allergy Shots: How They Can Help Your Animal
Allergy tests can be done to detect either food or environmental allergies. As discussed earlier, we will usually target food allergies first simply because they are much easier to treat. For food allergies we recommend a test called Nutriscan which uses saliva to test for food sensitivities. After administering the test, we get back a list of food ingredients that are allergens for your pet. If there is something on this list that can easily be removed from their diet, this is the ideal result.
Environmental allergy testing is the next option and tests for allergens that might be air borne in your pet’s environment. This type of test can either be done using an animal’s blood or through a technique called intradermal testing, which means pricking their skin with different allergens to see how the pet reacts. Research doesn’t point to one test being better than the other as each yields accurate results. Since we cannot usually prevent a pet’s exposure to environmental allergies, the practical outcome for environmental testing is to begin the pet on an allergy desensitization protocol. Once we know what a dog or cat is allergic to, we can start them on a regimen of allergy shots or oral drops. These shots or drops work by slowly exposing an animal to small amounts of allergens with the aim of desensitizing their immune systems over time. At best, this process takes months to yield results, so patience is definitely an asset during a trial of shots or drops. While many pets will show improvement, some will unfortunately not improve. As Doctor Richter says, “We all have some experience with allergies, either with ourselves or someone close to us, and these are rarely things you are going to fix completely. Allergies are usually a lifelong affair”. In these cases, it may be that the best option is to begin the pet on a steroid to see if it helps control their symptoms.
If you are wondering why we don’t just begin with allergy testing, the answer is that it is fairly expensive and takes a while to yield positive results; as such, it usually makes sense to begin with faster, more affordable avenues of treatment. When there isn’t a quick and easy fix, allergy shots and/or steroids or even immunosuppressants are usually the next best steps. At Montclair Veterinary Hospital and Holistic Veterinary Care, we know there isn’t one defined way to treat a pet’s allergies, and we are happy to explore and discuss the pros and cons of all possible treatment modalities with you. It can be a long process, but the good news is that there are many, many different avenues to take to help your loved ones get relief from their overactive immune systems.
If you have any questions about allergies or treatment options, please give Dr. Richter's office a call at (510) 339-2600!