Vet Blog: Information and Advice from Dr. Eric Barchas, DVM
07/14/08
 My eight-month-old female English Mastiff has spots of
hair loss on several places on her body. Our vet
tested her for mites. She doesn’t have any.
Tested her thyroid, it’s normal. He thinks it
might be a food allergy to chicken and corn, so he
changed her food from [a major commercial brand
to a hypoallergenic formula]. I add a little
canned food to her dry food and also use the
canned food to make her treats. She doesn’t
scratch herself excessively. Do you think we’re
on the right track to resolve this problem? I
would appreciate any advice you can give us.
Thank you,
Betty
TX
Based on your description of the spots (multiple spots, not itchy or inflamed), my first guess would have been puppy mange (also known as demodectic mange) is to blame. I wrote a somewhat extensive article on the topic a while back. You can read it by clicking here.
The test for puppy mange (called skin scraping) is pretty reliable. Nonetheless, in rare instances the test does fail to detect the mites involved in the syndrome. So one thing I recommend is that you keep puppy mange in the back of your mind as a possibility.
Certainly allergies (to food, pollen, fleas, or other environmental stimuli) can cause hair loss. But they usually cause itching and red skin as well. Thyroid problems can cause hair loss, but they are extremely rare in young dogs.
In my opinion, you have a couple of choices. The most aggressive tactic would be to perform biopsies of the affected areas. Samples of affected skin can be removed and sent to a laboratory for analysis. Biopsies are highly likely to lead to a diagnosis.
However, I’m not sure it’s necessary to go that far. If the bald spots are small and aren’t causing any irritation, it may be reasonable to take a wait-and-see approach.
Consider your dog’s age. An eight-month-old Mastiff is roughly equivalent to a 13-year-old person. Many 13-year-olds have acne. The blemishes associated with acne occur because the immune system is not fully matured. At this age, the immune system has a habit of over-reacting to some problems and under-reacting to others. The result is acne.
Your dog does not have acne per se. However, there is a very good chance that her patchy baldness is related to her immature immune system. If you wait a few months, the problem may resolve as her immune system matures.
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07/11/08
 I have a white pit and he seems to have allergies.
he breaks out all over his stomach and neck and
then scratches till he nearly draws blood. My vet
says to give him Benadryl. I’ve only given it to
him twice. What is your opinion on this?
Bonnie
Hazen, Arkansas, AR
My opinion depends on your dog’s response to the Bendadryl. Some allergies in pets are well controlled by Benadryl and similar over-the-counter antihistamines. Others are not.
Benadryl (diphenhydramine) is the most commonly recommended over-the-counter allergy medicine because it has a high margin of safety (although new concerns are arising about a link between Benadryl and cognitive decline in humans), and overdoses are rare. But in my experience, few pets experience dramatically reduced symptoms as a result of the drug.
If Benadryl does a good job of controlling your dog’s symptoms, then it probably will be the best bet for dealing with the problem.
If Benadryl doesn’t have much of an effect, then you may have to look into other treatments. The blog’s search function will help you find more information about hypoallergenic diets, allergy testing, allergen avoidance, flea control, omega-3s, and more potent medicines for allergies such as Atopica, Genesis, and prednisone.
Remember above all that allergies are impossible to cure. However, if you manage your pet’s problems properly, he should be able to live comfortably.
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06/04/08
This post was supposed to be published yesterday. Due to a computer glitch, it was not. I apologize.
Several different forms of allergy have been identified in dogs. I have mentioned flea allergy many times on this blog. Dogs also may be allergic to ingredients in food, or to detergents or other chemicals that contact their skin. Finally, like people, dogs may react to environmental allergens such as pollen, mold spores, and dust mites.
The final form of allergy mentioned above is known as atopy. The most common symptom of atopy is itching, especially on the feet, face, or abdomen. Dogs with atopy may also suffer from hair loss, skin infections, and ear problems. Atopy often occurs simultaneously with the other forms of allergy listed above.
The March/April issue of Banfield® Magazine contains a report based on data from a large chain of veterinary hospitals in the US. The report attempts to identify risk factors for atopy in dogs. Two findings stood out to me.
First, the study found that spayed and neutered dogs were approximately three times more likely to be diagnosed with atopy than their unaltered cohorts.
Second, the study identified the ten breeds most likely to suffer from atopy. Those breeds are: West Highland White Terrier, Bichon Frise, Jack Russell Terrier, English Bulldog, Staffordshire Terrier (also known as Pit Bull), Rat Terrier, American Bulldog, Havanese, Lhasa Apso, and Cairn Terrier.
I have some thoughts about the data. The report does not discuss whether spaying and neutering is truly a risk factor for atopy, or whether confounding factors might be influencing the numbers. On average, spayed and neutered pets are more likely to receive veterinary care than their fertile brethren. Is it possible that non-sterilized dogs with atopy simply aren’t being taken to the vet?
Also, I was surprised to see that Golden Retrievers and Labrador Retrievers did not make the top ten list of breeds diagnosed with atopy. So was Elizabeth Lund, the report’s author. Here is what she had to say on the matter.
Although Golden Retrievers and Labrador Retrievers have been thought to be more likely to have atopic disease, our results don’t support an increased risk for these breeds. They are both very popular breeds–consequently, by sheer proportion in our population, we may see more cases of atopic disease in these breeds than high risk breeds of lesser popularity.
The article definitely provides food for thought. However, I should point out that it was published in a corporate magazine rather than a more prestigious, peer-reviewed journal. Although the data are interesting, it might be wise to take them with a grain of salt.
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05/06/08
Pets are good for people. I firmly believe that, and I have mentioned it repeatedly on this blog. People with dogs get more exercise, on average, than people who don’t have dogs. (The other day I saw a very elderly man walking his Jack Russell Terrier. Without the dog, I have a hunch that gentleman would rarely leave the house.) Pets provide companionship and a sense of well-being to the people with whom they live. Cats and dogs are used in hospitals and nursing homes to cheer and comfort patients–with remarkable success. They can be trained to assist people with vision impairment, Parkinson’s disease, hearing loss, and even diabetes.
Of course, most of us on Catster and Dogster will agree that pets are good for our health and well-being. And a growing amount of scientific evidence is proving that pets benefit us in ways that are not so self-evident.
A recent article published by the AFP (a French global news agency) states that children who live with dogs may get an immune system boost from the family pet.
Blood tests showed that, in households with dogs, children were less at risk from becoming sensitised to pollens and inhaled allergens–the triggers for asthma and wheezing, allergic rhinitis and eczema–than counterparts in dog-less homes.
Sadly, the article also contains some disappointing news.
Oddly, though, the benefit seen in the children’s antibodies did not show through in terms of symptoms, the study found. Children with a dog were as susceptible to asthma and the other problems as counterparts without the pets.
This statement should not be construed to imply that the children were not receiving a health benefit from their canine companions. The study provides potent evidence that a household pet can help to stimulate the development of early childhood immune systems.
As scientists and doctors love to say: more research is necessary.
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04/16/08
I have a toy Poodle. His name is Batman and he has
itchy ears. Could they be to dry? I checked and there
are no mites, but his ears bother him constantly.
What would you recomend I do for his ears?
Thank you,
Kimberley
Pataskala, OH
Dogs with itchy ears may scratch their ears with their hind feet, rub their ears on the ground, or shake their head violently and repeatedly. A number of problems may cause ears to itch.
Allergies are a leading cause of itchy ears in dogs. Dogs may be allergic to fleas, food, or environmental substances such as pollen. Many dogs with allergies suffer from skin problems as well as ear problems, but for some dogs itchy ears are the only symptom.
Ear infections are another common cause of ear itching. Infected ears may also produce a foul odor, and redness or abnormal discharge from the ear may occur.
Foreign objects such as foxtails may lodge in ears and cause intense irritation. And there are many other problems that may lead to symptoms of itching. Plugs of ear wax that form near the ear drum, polyps that grow in the ear canal and mites that infest the ear are just a few.
The long and short of the matter is this: a veterinarian should examine Batman. The itching can only be treated after you know what is causing it.
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03/21/08
It is springtime in North America, and the pets are getting itchy! Over the last weeks, my inbox has been inundated with questions such as this one:
I have a 12-year-old Chihuahua that is constantly
scratching. I have tried giving her a bath about
every 2 - 3 weeks, but that hasn’t helped. What
else can I do to help her stop scratching? She
doesn’t have fleas and I haven’t seen anything
else on her. Sometimes she scratches till she is
almost bleeding. Could this simply be dry skin?
Please help. She is miserable.
Thanks,
DJ
Texas
When pets get itchy, allergies are the culprit nine times out of ten. And so, to those of you who have been writing in wondering why your pet is suddenly scratching or licking incessantly, my answer is that he or she probably suffers from allergies.
In a recent post, I touched upon some of the treatments for allergies. But, since so many pets are suffering from itching these days, let’s talk about allergies a little more.
There are three basic things that cause allergies in cats and dogs. Fleas are the number one culprit. Environmental allergens, such as pollen, mold spores, detergents, and dander are also common causes of itching in pets. Finally, proteins in foods can cause allergic reactions.
It is possible to run blood tests or skin tests that help to determine what, precisely, your pet is allergic to. They are pricey, but often worthwhile.
However, consider this. When I run blood allergy tests on my patients, I receive results reported in units that indicate the strength of the pet’s allergy to each offending item. The higher the number, the worse the allergy. A typical panel of results might look like this:
Ragweed pollen 373
Dust mites 254
Beef protein 339
Flea saliva 29,456
Every pet I have ever met who has allergies is allergic to fleas. And they are usually more allergic to fleas than to everything else combined. And, fleas are more active in the springtime.
So, what should you do if your pet is itching and you don’t want to run a bunch of tests? Go with the odds, and accept that fleas are probably the cuplrit. Apply a high quality flea preventative.
It does not matter if your pet does not “have fleas”. If your pet is allergic to fleas, then a single bite is all it takes to trigger itching and scratching. Consider this. I currently have three very itchy mosquito bites on my left arm. I do not “have” mosquitoes. But I know perfectly well that they are causing me to itch.
Unless you live in an area where there absolutely are no fleas, then the first thing to consider for an itchy pet is a flea preventative.
For the record, I am aware of only two places on Earth that are completely flea free: Denver, Colorado, and Mt. Everest base camp, Nepal. And, with global climate change occurring, there’s a good chance that fleas now exist in these places, too.
After applying a high-quality flea preventative, it may take several weeks or even months for the itching to go away. If it does not, or if your pet is really miserable, then go to the vet to look into some of the allergy tests and treatments that I mentioned in my previous entry.
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03/18/08
My Lhasa Apsos have allergies and have been tested.
I tried Atopica with no luck and it was expensive.
My vet said that giving my dogs predisone every
other day would not hurt them. Your thoughts
please.
Janeen
Mililani, HI
Allergies are frustrating, to be sure. Just ask anyone who suffers from hay fever. Allergies can make you miserable, and, for now, they cannot be cured. People actually move across the country to try to escape from their allergies. That is part of the reason why Arizona’s population has grown so rapidly in recent decades.
In pets, allergies usually cause skin problems such as hair loss, red skin, and itching. Ear infections also are common.
As I have mentioned, at the current time there is no cure for allergies. But there are several treatments. Some, such as flea control, soothing baths, omega-3 supplements, and hypoallergenic diets are simple and safe, and should be considered in every pet with allergies.
Others treatments, such as antihistamines, are generally safe, but not always effective. They are appropriate for some, but not all, allergy sufferers.
And then there are the bigger guns: allergy testing, followed by allergy shots, may help some pets. You mentioned that you have gone down this road without success. Genesis is a topical spray that significantly helps some pets. Atopica is another potent allergy treatment. It is expensive and generally effective, but it does not work in every pet.
Finally, there is the biggest gun of them all: prednisone. Prednisone is an anti-inflammatory steroid that is related to cortisone. It is simultaneously the best and the worst drug ever invented. No drug is more effective at treating allergies in pets. But prednisone also can cause a large number of side effects.
Pets who take prednisone long-term may suffer increased thirst, increased urination, weight gain, and personality changes. They may develop bladder or sinus infections. They are at risk of liver damage and diabetes.
However, not every pet who takes long-term prednisone suffers from these issues. Some pets can take prednisone for years without developing any problems. Others cannot tolerate the medicine for even a week.
So, to answer your question (finally): it may be safe for your dogs to take prednisone every other day. Or it may not. It depends on your dogs.
Here is what I recommend you do. First, exhaust all of the other treatment options that I have mentioned above, and make sure that none of them works.
If it turns out that only prednisone can make your dogs comfortable, then use it. But use the minimum effective dose. Monitor for the side effects that I mentioned above. And, very importantly, run comprehensive blood and urine tests every three to six months to ensure that the medicine is not having adverse internal effects in your dogs.
Finally, remember that some pets outgrow allergies over time. It may be worth your while to experiment (under the supervision of your veterinarian) with reducing or eliminating their prednisone doses periodically.
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My eight-month-old female English Mastiff has spots of
You have questions. 