from the berner-l

food allergies

It is quite common with food allergies that neither antihistamines or steroids help very much - and sometimes not at all. A food elimination diet must usually be used for at least 8 weeks as it frequently will take that long before the symptoms resolve. If you get some improvement in that time, but not completely, you should continue for another 4 weeks. Then, reintroduce the old food and see if the symptoms return - if so, you have definitive proof that she is allergic to something in that food. Return to the elimination diet, then gradually start adding in other foods individually and watching for a response - in this manner you can try to determine what exactly she is allergic to. If you feed her something she is allergic to (such as when you reintroduce her old diet) you will usually see a return of symptoms within a week.

Also, just because a pet has been eating the same food for a long time does not rule out the possibility of allergies. Most allergic pets will develop new allergies, and a new food allergy generally takes about 6 months to develop, though it can take longer. So, if you feed a dog a new food and they immediately (within the week) start showing problems, then they probably already had the allergy. (Skin problems and itching are usually signs of allergy; GI problems such as diarrhea, vomiting or gas may be allergy but more commonly are signs of intolerance - not necessarily the same thing; one involves the immune system, the other doesn't.) But if they've been on the food quite a while before showing signs, then they've likely developed a new allergy. Some derm vets I know recommend finding 2 different diets that work (different ingredients) and rotating those diets every 4-6 months to try to minimize the chances of developing an allergy to them.

Okay, about a food eliminination diet - you need to feed a novel protein source and a novel carbohydrate source - ingredients that the dog has ideally never been exposed to at all if possible. If that's not possible, then something that they may have only had once or twice as a treat. You cannot give anything else - no treats, no meds that contain food flavors (both Heartgard and Interceptor are out, and I think Filaribits is flavored as well, so are many of the pet vitamins), nothing! I usually recommend using whatever they are eating for their diet as treats - you can either take a canned diet and make balls, or a dry diet and grind it and add water then make balls or squares, and bake them for a good treat that most dogs don't realize is the same as their regular food. The best elimination diets are homemade - this way you have no question about what's in the food. There are also several commercial diets, both canned and kibble, that can be used for elimination diets, but all that are acceptable that I know of are veterinary diets. None of the generally available diets (what you can find in a grocery store, pet store or feed store) will work - at least none that I have seen, and I check regularly. Even the ones that say hypoallergenic and are "lamb and rice" or "venison and potato" or whatever, when you read the ingredients list, they ALL have something else in there, even is it's low on the list. Anything other than your chosen meat source or grain source is unacceptable, so the generic "meat meal" or "meat by-products" are not going to work.