By Dr. Rex C. Riggs, DVM ~ Best Friends Animal Hospital
It seems like this has been the worst season in years. Could be due to the fact we had such a warm winter and spring. I am sure many of you have reached your quota of Allegra, Zyrtec, or the plethora of other antihistamines available. Animals are suffering through their allergies too. In fact, animals have allergies to the same pollens that we do; the difference is that we most often have respiratory signs, such as sneezing and watery eyes, whereas dogs and cats have problems with their skin.
A very important difference to remember is the fact is that our allergies are caused mostly by histamine release, which is NOT true in animals. Animals’ allergies are mediated by other chemicals. This is why antihistamines are so effective for our allergies but only effective in animals 10-30 percent of the time.
So what is an allergy? It is the body’s exaggerated response to something it sees as foreign. Many people think allergies happen when the immune system is down, but it is just the opposite. Allergies form when an animal is exposed to some protein (an allergen) and the body produces specific cells called helper t-cells. These t-cells wait for the invader to come again (which happens seasonally with pollens) and when it does….POW…allergic signs. It normally takes at least two years for the animal to develop or become sensitive to the specific pollen allergen. Then, when it does, the animal develops seasonal allergies.
Now that we know all about the cause of allergies, what are the signs in our pets? So…..here is a list of the four most common signs I see when your pet develops allergies.
We see a lot of ear infections. What is an ear, but a tube of skin stuck to the side of a head? Ear infections in dogs are almost always the result of an allergy. The skin on the inside of the ear becomes inflamed and swollen, which shuts off the air coming into the canal and makes a magical environment for yeast and bacteria to grow.
Licking the paws:
A very common symptom of dogs, especially in small dogs, is licking their feet. How many of you have been awakened by the disgusting, slurping sound of your dog gnawing on his/her feet? Why the feet? They have direct contact with the ground where the pollens are, so there is often more inflammation there. Also, they are just easier to reach than any other part of the body.
There is normally a number of bacteria and yeast cells that take up residence on the skin. They live happily in balance, until something disrupts them. A dog chewing or scratching will do the job. We often see staph infections, especially in the lower belly area. Dogs must have a minimum of three weeks of antibiotics, because dogs’ skin cells turn over every three weeks. So if used for less than three weeks, it will reoccur…guaranteed. Very commonly, dogs will develop secondary yeast infections, which are often mistaken for inhalant allergies if not treated. I see a lot of “allergic dogs” become symptom-free after properly being treated for yeast.
Diarrhea and vomiting:
Just as in people, pets can become intolerant or allergic to a specific protein in the food. When this happens, they can show skin signs and/or gastrointestinal problems. There is a huge amount of misinformation out there regarding food allergies, pet foods, and how to treat them. Right off the bat, there is no quick and easy way to diagnose food allergies. No blood test is reliable in detecting the causative protein. The only way to diagnose is to perform a food trial with a food with a single protein, which the dog has never been exposed to, and a single carbohydrate. Often, people run to the local pet store to find a hypoallergenic diet. You will find many that make that claim, but unfortunately there are no true hypoallergenic diets sold at pet stores. The quality control of the companies making the foods is lacking. Many companies do not even make their own food. A study was performed by Dr. Raditic and associates (Raditic DM, Remillard RL, Tater KC. “ELISA testing for common food antigens in four dry dog foods used in dietary elimination trials.” Journal Animal Physiology Animal Nutrition. October 2010). They analyzed four popular novel protein diets bought from a pet store to see if they were contaminated with any proteins other than the one listed on the label. All the diets had other meats and proteins present, making the food worthless for allergy food trials. To rule out food allergies, a prescription diet is needed and the food trial can take up to 16 weeks. The proteins that most commonly cause allergies are beef, dairy, chicken, and eggs. Interestingly enough, grains are not a common cause of food allergies. Less then one percent of dogs have intolerance or allergies to grains. High protein, low grain diets are the latest fad in pet foods. It is probably a result of the recent increase in people being diagnosed with gluten intolerance.
Finally, if you so suspect an allergy of any kind in your pet, please consult your veterinarian to see how you can discover and manage your pet’s condition effectively.
Do you think your dog has allergies after reading this?