Find more dog breeds here!


Total Pageviews

Saturday, February 5, 2011

Food allergies

I've blogged many times on allergies in dogs and cats. The two main categories of allergies in companion animals are atopy (environmental allergies) and adverse food reactions (food allergies).
Symptoms of both can be very similar, which include chronic otitis (ear infections), itchiness of the ears, face, paws, belly, etc., non-itchy or itchy infections along the entire dorsal neck and back and other dermatological manifestations. Most (but not all) pets with food allergies are ITCHY.
Some (but not all) dogs and cats with a food allergy, will have gastro-intestinal symptoms such as vomiting, diarrhea, and flatulence.
In dogs, the ingredients most commonly responsible for food allergies include chicken, beef, dairy, lamb, eggs, wheat, less often corn and soy. In cats, fish, beef, and dairy are big ones.
What is so important to understand is that any food can eventually become an allergen in any pet, it just takes time to develop an immune response to the offending food.
Pets that present with allergy symptoms at either a very young age or a very old age are more likely to have a food allergy than an environmental one (though this is not set in stone).
Some laboratories run diagnostic tests that look for specific antibodies (called IgEs) against different antigens found in food, however dermatologists have taught us that these tests are far from accurate. These serum IgE blood tests are far more accurate against environmental allergens (like dust mites, grasses, trees, etc). The only way to find out if your pet has a food allergy is to try a limited-antigen diet, or a novel diet (containing ingredients that the pet has NEVER before consumed in its lifetime) for a total of 10-12 weeks, with no cheating! Do not choose these foods on your own, but rather have your vet help you choose. In my experience, pet owners often have the right idea by changing foods, but invariably never choose the appropriate ones to rule out food allergies.
And don't run for organic-shmorganic foods. A cat allergic to beef will also be allergic to beef in a bag of food that costs a thousand bucks!
If you suspect food allergies in your pet, talk to your vet about it.

A cat with a food allergy. Photo taken from:


Sarah said...

Both of my dogs have food and environmental allergies and the hardest thing I have is that my dogs are allergic to a range of things and since most of them are hard to eliminate from the environment the symptoms are hard to eliminate, but every time I ask the vet for stuff to alleviate symptoms he says "get the allergies under control" and leaves it at that. My one dog licks his feet raw, but he is allergic to dust mites, an array of pollen, molds, grasses as well as foods. I can't keep them all away from him and the shots haven't worked, so I ask for tips or something for his feet, but get nothing.

The other thing I hate about the allergies is that every issue I get with my dogs is blamed on it. I noticed discharge from one of my dog's eyes and the vet said it was from the allergies--well it turns out she has juvenile cataracts in both eyes, which he might have seen if he had looked. She had gone completely blind in one eye before I asked for a second opinion.

Sorry for the rant.

I do like to be mean to pet store clerks by asking them to find a prepared food my dogs can eat, because they are allergic to rice and potatoes and beef and fish and even more, so they can only eat the v/d ultra allergian free food, or prepared food.

emilene said...

My little 5 year old Yorkie has been suffering from an allergy that is yet to be identified. We have spent a fortune at the vet and because she manifests so bad, the only option has been cortisone injections and antibiotics. I DON'T want to do this anymore as she is so tiny, weighs 2,7kg. I've changed her diet to Royal Canine's hypoallergenic but after a month it flared up again. She gets a rash around her neck and around her private parts - I'm really starting to think it has something to do with grass. Knowing that the tests are not conclusive and they cost an arm and a leg, I'm not going to have that done. Do you have any suggestions of what else I can try?

Thanks a mil for a wonderful site!

TorontoVet said...


Cytology should be performed on the dog's paws to make sure there's no yeast present. Yeast can greatly exacerbate a dog's itchiness.
Your dogs can be allergic to many things, but I don't think they're allergic to all of the things you propose.
Serum allergy testing (with intradermal skin testing) can be quite successful at finding out what environmental allergens the dog is allergic to.
In this case, I would use a commercial diet or homemade diet (see vet for recipe) that contains a novel protein and novel carbohydrate. The skin and blood testing will be mildly-moderately expensive but may help enormously. So will the food trial.
Be patient, be nice to store clerks, and good luck!

Emilene, Yorkies for some reason have higher incidence of ringworm (a dermatology professor told me this personally), don't ask me why. Have your vet do a mycology (fungal culture).
Second recommendation: ask your vet for referral to see a veterinary dermatologist.
Feedback is always appreciated!

emilene said...

Thank you so much - she had to have more injections today and I only read your suggestions now but will follow up for sure. The so-called 'Bath diet' has also been suggested to me now by my vet - they seem to have had great results with that. I'm going to do my homework and will let you know how it goes. Thanks again!

Nicki said...

Graet blog! I write a blog about vet med and dog agility and I'd love it if you would add it to your blogroll

TorontoVet said...


Forgot to add: Atopica (or cyclosporine) may be the medication you are looking for. Talk to your vet about it.

Martha said...

ah, good (timely)topic.

My 10 year old (orange) DSH has had for 4 years in a row an outbreak of Eosinophillic Granuloma but ONLY in middle January to late February.
We finally have a solution(after 3 years of trying various treatments)>>> a week of Surolan !
he gets Lamb only- no other protein,so the diet is controlled as best as we can-but as we know cats are climbers and jumpers.....

right after New Years I keep a watchful eye on his back near the tail- but this year it started up near his collar.

Cool Springs Veterinary said...

A lot of animals that move to this area seem to develop food allergies.

TorontoVet said...

Cool Springs,

If many pets without previous allergic skin disease move to your area and start to develop allergy symptoms, I cannot imagine that they are developing food allergies but rather environmental ones.
Thanks for commenting!

dental vet said...

The serum allergy testing (with intradermal skin testing) can be quite successful at finding out what environmental allergens the dog is allergic to. In this case, I would use a commercial diet or homemade diet (see vet for recipe) that contains a novel protein and novel carbohydrate.

Animal veterinarian raleigh said...

Ya,There are so many allergen presents in environment that affect the the activity of your dog (pet)

Blanca said...

I ran into this blog by random chance at around 2:30AM while doing extensive "research" about my cat's over-grooming problem. I have taken her to 3 vets including a cat specialist and no one could find anything wrong with her. The final vet, the specialist, put her on a special diet, Royal Canine Hypoallergenic Formula, with selective ingredients. I think it just has rabbit and something else I cannot remember. It is VERY expensive. Over 53 dollars for a very small bag. She hates it, by the way, so it lasts her about a couple of months. After a steroid injection and being on this food for about a month, I decided to change her litter to pine pellets like the ones used in horse stalls to keep them dry because I read online somewhere that some people use that for cats with environmental allergies. I have just noticed a rash on her belly that looks like little pimples and I am very concerned which is why it is so late and I am still up "researching". What should I do? How can I help my cat? I put an E-collar on her to stop her from licking herself. She licks so much she makes herself bleed. She also scratches herself until she bleeds. I just noticed the rash today. The rash has white tips. Does she need to see another vet? She is about 10-12 years old. I took her in as a stray/feral cat years ago and have had no medical problems until now. She is spayed and is indoors only. I feel like there is nothing else I can do for her but there should be something else.

TorontoVet said...

Bianca, I am so empathetic to your concerns. However, I'm equally concerned about you not voicing your concerns with the specialists. This occurs often in general practice: pets are referred to specialists to help diagnose and manage difficult cases. More often than not, the pet owner returns to the GP and asks, "What do I do now?" 1) This isn't fair to the GP as the specialist made recommendations with the presumption that you would follow them. If there are cost concerns, they should be voiced up front to the specialists - remember they ARE SPECIALISTS whose prices are forcibly, and deservedly, higher.
Your cat is a good candidate for intradermal (skin) allergy testing and possible "vaccines" or desensitization if indicated. The cat should be on a novel protein and carbohydrate diet (or hydrolyzed protein diet) for a minimum of 12 weeks with NO CHEATING!
Skin scrapings and possible biopsy should be considered in these cases but remember, if a biopsy diagnoses an allergy, it still doesn't tell us what the pet is allergic to. Atopica is an anti-allergy medication that is quite safe in pets, I'd discuss it with the vet.
I'd return to the specialist and voice your concerns. Best of luck and I hope the cat finds some relief soon.

Emily said...

Thank you so much for your blog, I am so thankful to have run across it.

I adopted a devon rex about 6 months ago and the poor thing has terrible allergies. We were on a stict z/d diet for several months, the symptoms were controlled, so we decided to gradually try another food that was a little less expensive -- but still high quality. She was fine on the other food for several weeks but had a couple flare-ups, so I returned her to z/d food -- after 3 weeks the symptoms are worse than ever. She has itchy bumps all across her back, neck and stomach, and she has licked them raw -- some of them to the point of bleeding. I have seen my vet several times, and have put her back on a steroid and anti-inflammatory drug.

My question is, after I took her off of the z/d she got worse, but is it common for the flareups to be so delayed and so severe? I will certainly keep her on a strict z/d diet, but would you recommend a cortisone injection to ease her suffering? She is also has diarrhea, which I assume is another complication of her food allergy.

She was drinking from our betta fish bowl (which I have since covered). Is it possible she could have an allergic reaction from the small amount of fish food I put in that water? I'd appreciate any suggestions you can offer. Thank you so much!!

Anonymous said...

My cat suddenly developed red itchy sores around her ears, top of head, back of head and down the spine after many years of no issues at all. The vet diagnosed it as a food allergy. Trying to figure out what she was allergic to was difficult. I had her on vet hypo-allergenic biscuits and wet food but there was no improvement. In fact she seemed to get worse and in the end after seeing her lose weight and fur and going downhill fast I gave up and put her on back onto raw beef and veal. However while she physically got better she still had the sores and I had to continue the regular vet visits for injections and pills. Then I discovered raw kangaroo meat and it's all been positive news since. I also have her on grainfree biscuits and have recently introduced tuna (without the fillers and other by- products found in canned food) back into the diet. We haven't been to the vets for allergy issues for 2 years now.

Cliff Mardinger said...

Food allergy is a diagnosis of exclusion. While I agree with the diagnosis, you can't look at an animal and say, "that's food allergies!"
Grains aren't always the culprit: beef, chicken, eggs, dairy, etc, can all be culprits in food allergies. Sounds like you have a diagnosis in this case. However, if the cat is eating nothing but protein (meat & fish), she is in for serious dietary deficiencies in the long run. Talk to your vet about making it more complete with a vitamin and mineral supplement.
Thanks for sharing your success story.