By Dr. Rex Riggs -the owner of Best Friends Veterinary Hospital in Powell, Ohio.
Boy…is it allergy season again in Ohio! It seems like this has been the worst season in years. It could be due to the fact we had such a warm winter and spring. I am sure there are many of you that have used 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, where dogs and cats have problems with their skin.
A very important difference to remember is the fact is that our allergies are caused mostly due to histamine release and which is NOT true of animals. Animals’ allergies are mediated by other chemicals. That is why antihistamines are so effective for our allergies but only effective in animals, 10 -30 % 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 with pollens happens seasonally) and when it does….POW…allergic signs. It normally takes at least 2 years for the animal to develop, or become sensitive to the specific pollen allergen, then when it does, then animal develops seasonal allergies.
Now that we know all about the cause of allergies, what are the signs in our pets? So…..here is my list on the 4 most common signs, I see when your pet develops allergies.
- Ear infections:
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 and that shuts off the air coming into the canal and it makes a magic 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 wakened 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. And also, I think they are just easier to get to than any other part of the body.
- Skin infections:
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 3 weeks of antibiotics because dogs’ skin cells turn over every 3 weeks, so if used less then 3 weeks, it will reoccur…guaranteed. Very commonly dogs will develop secondary yeast infections, which if not treated, are often mistaken for inhalant allergies. 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 one 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 other proteins than the one listed on the label. All the diets had other meats and proteins present, therefore making the food worthless for allergy food trials. To rule our food allergies, a prescription diet is needed and the food trial can take up to 16 weeks. The proteins that cause allergies most commonly are beef, dairy, and chicken, including eggs. Interestingly enough, grains are not a common cause of food allergies. Less than 1% 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 Dogs and cats are not humans.