intense allergy season for us and our pets. Allergies to fleas (which never really went into dormancy this past winter), pollens, grasses and trees are already starting to rev up this Spring.
We won't bore you with a lot of immunology here, but in order to fully understand allergies and their affects on our pets it is important to have at least some knowledge of the pesky Mast Cell and it's role in our immune systems. Mast Cells are a part of our immune system designed to protect us against parasites. They contain a variety of granules containing some very potent inflammatory enzymes designed to kill off invading parasites...the most well known of these enzymes is Histamine. Stimulation of Mast Cells causes them to detonate like little land mines, giving off all of these enzymes. Ideally this reaction harms the offending parasite and calls in other immune system cells to join in the "battle". Unfortunately many other "foreign substances" have antigens (surface proteins) that are similar in structure to the antigens found on parasites. These substances also cause the Mast Cells to degranulate leading to a local inflammatory reaction (redness, itching and swelling). In people, the largest concentration of Mast Cells exist in our Respiratory Tract. So Mast Cell degranulation (or an allergic reaction) usually leads to dry, itchy eyes; a dry, scratchy throat; a runny nose and all of the other symptoms we commonly associate with Seasonal Allergies or "Hay Fever". In our dogs and cats, the largest concentration of Mast Cells are actually in the skin....specifically in the skin around the eyes and muzzle; ear flaps; in between the toes; armpits; groin and under the tail. So, instead of our respiratory symptoms dogs and cats experience dry, itchy skin... resulting in the scratching/licking/chewing/biting that drives so many of us living with an allergic pet crazy!
Since it is highly unlikely that an allergic pet is going to be able to avoid exposure to allergens (pollens can travel miles on a good breeze), we are left with the task of trying to prevent and treat the results of an allergic reaction. As you will
see from the variety of options we are going to discuss, there is NOT always a
simple solution to your pet's allergies. PATIENCE is needed to find the specific therapy that will work for your specific pet.
First we will discuss Steroids or Cortisone Therapies. This class of medication is VERY effective at suppressing the itch and allergic reactions caused by Mast Cell Degranulation....most pets being treated with a steroid (such as Prednisone) can become itch free and symptom free. There are a variety of oral and injectable formulations available to make this treatment option both inexpensive and easy to use. So why isn't this the end of the discussion you may wonder? The negative aspect of the steroid family is that there is a fairly significant "Side Effects Paycheck" tied to their use. Increased thirst, increased urination, increased appetite, panting and some behavioral changes may be noted in the short term and immune system suppression, high blood sugar, liver stress, kidney stress and other organ damage can be seen with long term use. This is not necessarily a class of drugs to be avoided, BUT one that we need to use cautiously and with respect for both it's potent benefits and risks. Ideally a steroid is used to knock the itching down to a low enough level that some of the other control measures will have a chance at preventing the itching from coming back. Our goal is always to use the lowest dose of steroid with the longest interval between doses possible to keep our patients comfortable.
The next most common treatment modality used for allergic pets are the Antihistamines or Histamine Blockers. Benadryl, Claritin and Allegra are some examples from the long list of options we have to choose from. Antihistamines are very safe to use long-term, but they are much less potent of an anti-itch
medication than steroids. In fact, antihistamines are much better at preventing
itch than they are at reducing itching once a certain threshold has been crossed. It is important to remember that choosing a specific antihistamine for your pet is a matter of trial and error.....not every pet will respond to every antihistamine and there is no way to predict which one an individual pet will respond to the best. We start with an antihistamine that "usually" works, but occasionally several 2-3 week trials may be necessary before we find the best fit for your pet....so please be patient during this process.
Omega 3 Fatty Acids or Fish Oil Supplements have many benefits on many organ systems within the body. In relation to allergies, they replenish hydration and pH balance to the skin and hair coat leading to a healthier, more comfortable protective barrier. A well hydrated skin layer will keep allergens out of the system better and we all know how itchy dry skin can be! Additionally the Omega 3 Fatty Acids actively work to block one of the inflammatory cascades within the skin, so they do also have an anti-itch effect. And best of all they work synergistically with antihistamines....meaning they actually help antihistamines to work better than they would if given alone! There are no real dangers to using Fish Oil Supplements, however the dose tolerated is usually limited by gassiness and/or soft stool. These nuisances can be addressed by a simple reduction in the
amount given. Since these are nutritional supplements and not medications it
usually takes 6-8 weeks for levels to build up in the system before any benefit
should be expected.....again with that annoying patience requirement!
Moisturizing Shampoos, Conditioners and Topical Sprays can often be useful in managing your pet's allergies. The goal again is to replenish hydration and pH balance to the skin and hair coat while rinsing off as many of the allergens as possible. Appropriate shampoos (Pet Designed Oatmeal & Aloe Vera Based Shampoos) can be used once or twice weekly and some of the topical sprays can be used on a daily basis. It is important to be sure to bathe your pet in lukewarm water (not hot) and allow the lather to contact the skin for 10-15 minutes prior to rinsing to get the maximal benefits of these products. Some of the Conditioners and Lotions are even designed to be left on and not rinsed off at all. Some Lotions and Sprays contain medications to reduce the itchiness of the skin or to control the secondary skin infections that are so common in allergic pets. Looking for a simple "home remedy" to help your pet's itch? Try using Avon Skin-So-Soft diluted in water (1 part lotion to 10 parts water) in a spray bottle....this creation can be spritzed onto the skin and rubbed in on a daily basis to provide a comfortable, hydrated and healthy allergen barrier.
Another rather simple, but highly effective method to reduce your pet's allergy woes is to thoroughly wipe him/her down after coming in from outdoors. Keep a towel by the door and before your pet comes back inside wipe off his/her feet very well ("like they stepped in a mud puddle") and a quick wipe-down of the nose/face/body to strip away as many of the allergens as possible before they have a chance to be absorbed into the skin.
Fleas can be a nuisance to any pet, but if you live with an allergic dog or cat it is absolutely essential that you are practicing good Multi-Modal Flea Control in your household. Flea allergies and reactions to flea bites are some of the most
potent antigens to the dog or cat immune system! Almost every pet that has Seasonal Allergies also has some degree of Flea Bite Allergy to their reaction. Unfortunately, for allergic pets there is not a "one size fits all" solution to flea control...and often times more than one product will be required to keep your pet flea bite free.
It is important to consult your Veterinarian about the possibility of secondary infections that are so common in allergic pets. Bacterial and yeast infections of the skin and bacterial and yeast infections of the ears must be appropriately treated if we ever hope to regain a good level of comfort for an allergic pet. Your Veterinarian will need to diagnose these infections, prescribe a specific treatment and (most importantly) follow up to ensure that an infection has completely resolved with the prescribed therapy. A combination of topical and systemic/oral medications are usually needed and occasionally more extensive testing (such as a Culture & Sensitivity Evaluation) may be needed to get full resolution of your pet's secondary infections.
Thus far, we have been discussing uncomplicated or "routine" Seasonal Allergies. But what do we do for the more difficult to control allergic pet? If a pet has failed to respond sufficiently to the above therapies your Veterinarian will likely offer the option of having a referral to a Veterinary Dermatologist who specializes in diagnosing and treating diseases of the skin and ears (including Allergic Dermatitis). While these referrals are not inexpensive they are often the quickest and most effective route to getting resolution of a complicated allergy case.
Your Veterinarian will likely also discuss the use of a medication called Atopica (a Cyclosporine-based treatment). Most people have heard of Cyclosporine in the setting of preventing organ rejection in transplant patients. Atopica modulates the immune system in dogs and cats in such a way as to minimize allergic reactions. It is effective in 60-70% of pets and when it does work, it usually is as effective as steroids without the nasty side effects. What is the down side? Cost! Using Atopica can become a financial burden for medium to large sized dogs, but sometimes it may be one of the only effective means of keeping a pet comfortable.
Elimination Food Trials will likely need to be addressed in order to rule out Food Allergy as a component of the difficult to control allergic pet's disease process. This is an extensive subject all on its own and will be discussed in more depth in another blog entry!
Finally, Allergy Testing and Hyposensitization Injections/Immunotherapy can be very helpful in gaining the upper hand with difficult allergies. Intradermal Skin Testing by a Veterinary Dermatologist or Blood Allergy Tests performed by your Primary Care Veterinarian can be used to determine what environmental allergens are most likely affecting your pet. This information is used to formulate a specific mixture of Immunotherapy to try and "trick" your pet's immune system into not over-reacting to these allergens when encountered in the environment. Immunotherapy is effective in 60-70% of pets.....it is usually not a cure-all, but rather another tool to help the other therapies work more effectively. One of the biggest draw backs for some pet owners is that this approach requires injections to be given either by the pet owner or by frequent trips to the Veterinary Office to have them administered.
So, as you continue to seek ways to enjoy the summer months with a happy and comfortable companion by your side, don't become discouraged if your pet's allergies seem to be an ongoing issue. You are not alone! Seasonal Allergies are a very common ailment and with some patience, follow-up and communication with your Veterinary Health Care Team.....very manageable. So get out there and celebrate summer!!!