|
Archive-name: dogs-faq/medical-info/canine-allergies
URL: http://www.k9web.com/dog-faqs/medical/canine-allergies.html Last-modified: 07 Nov 1997 See reader questions & answers on this topic! - Help others by sharing your knowledge ======= There are nearly 100 FAQ's available for this group. For a complete listing of these, get the "Complete List of RPD FAQs". This article is posted bimonthly in rec.pets.dogs, and is available via anonymous ftp to rtfm.mit.edu under pub/usenet/news.answers/dogs-faq/faq-list, via the Web at http://www.zmall.com/pet_talk/dog-faqs/lists/faq-list.html, or via email by sending your message to mail-server@rtfm.mit.edu with send usenet/news.answers/dogs-faq/faq-list in the body of the message. This article is Copyright 1997 by the Author(s) listed below. It may be freely distributed on the Internet in its entirety without alteration provided that this copyright notice is not removed. It may NOT reside at another website (use links, please) other than the URL listed above without the permission of the Author(s). This article may not be sold for profit nor incorporated in other documents without he Author(s)'s permission and is provided "as is" without express or implied warranty. ========== Skin and Allergy Problems in Dogs Author Cheryl Minnier, cminnier@epix.net Copyright 1996 by the author. _________________________________________________________________ Table of Contents * Introduction * Inhalant Allergies * Food and Flea Bite Allergies * References _________________________________________________________________ Introduction The most common medical complaint we see in dogs is skin or ear related. Unlike humans who react to allergens with nasal symptoms, dogs react with skin problems. These problems may range from poor coat texture or length, to itching and chewing, to hot spots and self mutilation. Allergies may also play a part in chronic ear infections. To make matters more difficult to diagnose and treat, thyroid disease may add to the problem as well. In order to overcome these frustrating symptoms your approach needs to be thorough and systematic. Shortcuts usually will not produce results and only add to owner frustration. This article will cover diagnosing and treating; inhalant, food, and flea allergies. I will also briefly discuss thyroid disease and immune mediated disorders. Remember, your best source of information is your vet. Many vets are now recognizing the need for holistic allergy treatment instead of the tried and true (and possibly ineffective or dangerous) standby of corticosteroids. If your vet is not helpful, keep looking until you find someone you are comfortable with. You need to remember though, that the success or failure of treatment will rest mainly on you. There is no magic pill to deal with these problems. Unfortunately, there is also no "cure", only systematic treatment options. Much of the information below is taken from "Guide to Skin and Haircoat Problems in the Dog" by Lowell Ackerman, DMV. _________________________________________________________________ Inhalant Allergies Substances which can cause an allergic reaction in dogs are much the same as those which cause reactions in people including pollens, dust mites and molds. A clue to diagnosing these allergies is to look at the timing of the reaction. Does it happen year round? This may be mold or dust. If the reaction is seasonal, pollens may be the culprit. Symptoms of inhalant allergies include: SCRATCHING, BITING, CHEWING AT FEET AND CONSTANT LICKING. The itching may be most severe on feet, flanks, groin and armpits. Dogs may rub their face on the carpet. Ear flaps may become red and hot. Chronic ear infections may follow. Skin becomes thickened, greasy and has a strong odor. Hot spots may develop due to irritation from constant chewing or scratching, which is then followed by infection. Allergies have also been implicated as a possible cause of Acral Lick Granulomas, a frustrating, treatment resistant condition whereby the dog creates a sore on his skin from constant licking DIAGNOSIS If a dog has the above symptoms and responds well to the treatment measures outlined below, no further diagnostic tests may be needed. If the problem is severe and does not respond to simple measures, allergy skin testing can be done. A portion of the skin is shaved and a variety of substances are injected into the skin to see if they provoke a reaction. If so, an individual series of injections are formulated to give the dog over a period of time (there are blood tests designed to identify allergens without the skin testing, however their efficacy had not been proven. They should be reserved for cases where skin testing is not possible). TREATMENT OPTIONS Symptomatic Therapy Treating the dogs symptoms may include; cool baths with or without colloidal oatmeal, Epsom salts, or medicated shampoos. This can be done frequently but provides only temporary relief. Caution should be used with sprays and ointments because many contain potentially harmful substances. According to Dr. Ackerman, Dermacool is a safe spray containing witch hazel. Cortispray is a low dose, nonsystemic cortisone spray which can be safely used for short periods of time. Immunotherapy Allergy shots are very safe and many people have great success with them, however, they are very slow to work. It may be six to twelve months before improvement is seen. I spoke with Dr. Christine Johnson, a veterinarian with the dermatology department of the University of Pennsylvania, about intradermal skin testing for inhalant allergies. She reports the average success rate is 70-75%. This rate is for dogs showing any improvement at all. At U of P. the cost for the procedure is $69.00 for the exam, $122.00 for the sedation and testing, and $85.00 for the first 5 months worth of vaccine. After that vaccines are purchased in 7 month supply for $65.00. Substances that are tested include cats(!), feathers, wool, molds, dust, trees, insects, plants and pollens. Before testing, your pet must be free from all steroids, oral or injected (including those found in ear and eye medicines) for a specified period of time in order for the test to be valid. In all about 60 different substances are tested for. Corticosteroids These compounds reduce itching by reducing inflammation. Unfortunately, they also affect every organ in the body. According to Dr. Ackerman, steroids should be considered only when the allergy season is short, the amount of drug required is small or as a last resort to relieve a dog in extreme discomfort. Side effects can include increased thirst and appetite, increased need to urinate and behavioral changes. Long term use can result in diabetes, decreased resistance to infection and increased susceptibility to seizures. You can recognize steroids by the suffix "-one", such as cortisone, dexamethasone, prednisone..etc.. In short, alternatives to steroid therapy should always be considered. Antihistamines Antihistamines can be used with relative safety in dogs. About one third of owners report success with them. The major drawback, as with people, is sedation. Dr. Ackerman recommends that a minimum of three different types of antihistamines be tried before owners give up on this therapy. According to Dr. Johnson, the most common problem with this type of treatment is that owners give the drugs at doses that are too low. Check with your vet on correct dosing. Examples of antihistamines commonly used for dogs include: Tavist, Benadryl, Chlortrimeton, Atarax and Seldane. Personally, I have seen the best results with Atarax. Omega-3 and Omega-6 Fatty Acids These fatty acids are natural anti-inflammatory agents. They reportedly are helpful in 20% of allergic dogs. My own experience puts this figure a little higher. They are certainly worth a try because they are not harmful and have virtually no side effects. Omega-3 fatty acids are found in fish oils (especially krill and cod) and omega-6 fatty acids are derived from plants containing gamma-linolenic acid (GLA), such as oil from the evening primrose. These supplements are different from those sold to produce a glossy coat. They tend to reduce inflammation that may lead to skin sores but are not as effective in reducing itching. Products that contain both omega-3 and omega-6 fatty acids include: Omega Pet, Derm Caps, and EFA-Z Plus. Environmental Control If you know which substances your dog is allergic to avoidance is the best method of control. Even if you are desensitizing the dog with allergy shots, it is best to avoid the allergen altogether. Molds can be reduced by using a dehumidifier or placing activated charcoal on top of the exposed dirt in your house plants. Dusts and pollens are best controlled by using an air cleaner with a HEPA filter. Air conditioning can also reduce circulating amounts of airborne allergens because windows are then kept closed. Prevention While there is nothing you can do to prevent a rescue dog from developing allergies, breeders should be aware that allergic dogs SHOULD NOT BE BRED!!! Dr. Johnson confirmed that there is clinical proof that allergies are inherited! _________________________________________________________________ Food and Flea Bite Allergies The previous section of this article dealt with atopy or inhalant allergies. This article will deal with food allergies or to be more precise, food sensitivities. Much of the information presented here is drawn from "Hair and Skincoat Problems in the Dog" by Lowell Ackerman D.V.M. and an interview with Dr. Scott Krick of the VCA Sinking Spring Veterinary Hospital. Food allergies account for only about 10% of allergy problems in dogs, however they are easily treated so it makes sense to test for them if you suspect they may be the culprit of your dog's skin problems. Like inhalant allergies, food sensitivities primarily manifest themselves with itchy skin. Other symptoms include anal itching, shaking of the head, ear inflammations, licking front paws, rubbing faces on carpeting and rarely vomiting, diarrhea, flatulence, sneezing, asthma like symptoms, behavioral changes or seizures. Many people don't suspect food allergies as the cause of their dog's itching because their pet has been fed the same food all its life and has just recently started having symptoms. However, animals can develop allergies to a substance over time, so this fact does not rule out food allergies. Another common misconception is that dogs are only sensitive to poor quality food. If the dog is allergic to an ingredient it doesn't matter whether it is in premium food or the most inexpensive brand on the market. One advantage to premium foods is that some avoid common fillers that are often implicated in allergic reactions. DIAGNOSIS Dogs are not allergic to a dog food per se, rather they react to one or more of the ingredients in the food. Some of the most common culprits are beef, pork, chicken, milk, whey, eggs, fish, corn, soy, wheat and preservatives. Many animals are now developing allergies to lamb as well. This was once thought to be very hypo-allergenic, but the more it is used, the more sensitivities are springing up. The first step in diagnosing a food allergy is to eliminate all possible allergens and feed ONLY a homemade diet with ingredients the dog has never eaten before. The diet should be a protein and a starch. Good examples are one part lamb, rabbit or venison mixed with two parts rice or potatoes. NOTHING else can be fed during this time; no biscuits, chewable heartworm pills, chew toys or any table scraps!! You must also keep the dog away from feces if he or she is prone to eating stool. This diet should only to be fed for a short period, while testing for allergies. It is not nutritionally complete enough for long term use. Check with your veterinarian before beginning the test. If the symptoms improve during the trial diet, go back to the original food for several days. If symptoms reoccur you know that something in the food is causing the reaction. The next step is to return to the trial diet and add one new ingredient a week (i.e. add beef for one week and if no symptoms occur add corn the next week for one week). Once you have discovered the allergen you can look for a commercial food which does not contain that ingredient. According to Dr. Ackerman, approximately 80% of dogs with food allergies can be maintained on a commercial hypo-allergenic diet. Some of the common hypoallergenic diets include "Nature's Recipe", "Sensible Choice" and "Natural Life". "Nature's Recipe" makes a lamb and rice food, a venison and rice diet and a vegetarian diet, none contain chemical preservatives. "Natural Life" also makes a preservative free, lamb and rice food called Lamaderm. "Sensible Choice" is a third brand that is considered hypoallergenic because it contains neither wheat or corn and comes in a lamb and rice formulation. Note: just because a food is labeled "Lamb and Rice" do not assume it is hypoallergenic. Many contain wheat, corn, soy, beef or preservatives. This process of elimination is trying and time consuming. You should be aware that it may take up to 10 weeks to see an improvement. However, it is the best method available to test for food allergies. You may wish to try switching your dog to one of the foods listed above for a month as a trial. If the dog shows improvement you know you are dealing with a food sensitivity, you just won't know which ingredient to avoid. If there is no improvement, you will need to begin the elimination testing. Flea Allergies This type of reaction, again usually severe itching, is not to the flea itself but rather to proteins in its saliva. Dr. Ackerman writes that dogs most prone to this problem, interestingly enough, are not dogs who are constantly flea ridden, but those who are exposed only occasionally! A single bite can cause a reaction for five to seven days, so you don't need a lot of fleas to have a miserable dog. To test for flea allergies, a skin test is performed which must be read in fifteen minutes and again in forty eight hours. Unfortunately injections to desensitize are not very effective because it is hard to collect enough flea saliva to make a serum! For dogs with this problem a strict flea control regime must be maintained. We would caution you, however, against using strong chemical preparations on your dog. Often times the flea control program produces more harmful effects than the fleas, including seizures and skin problems, so please use caution. _________________________________________________________________ Third section, coming soon! _________________________________________________________________ References Ackerman, L.: _Guide To Skin and Haircoat Problems in Dogs_. Alpine Publishing, 1994: 7-19. _________________________________________________________________ Skin and Allergy Problems in Dogs FAQ Cheryl Minnier, cminnier@epix.net Hosted by K9 WEB User Contributions:
[ Usenet FAQs | Web FAQs | Documents | RFC Index ]
Send corrections/additions to the FAQ Maintainer: sminnier@epix.net (Cheryl Minnier)
Last Update March 27 2014 @ 02:11 PM
|
Comment about this article, ask questions, or add new information about this topic: