Food allergies are common in dogs. It is the most common form of allergic skin disease second only to fleas.
Most dogs are first diagnosed with food allergies when they are young, under 3 years of age. Certain breeds including labs, golden retrievers and pit bulls seem to be predisposed but it can occur in any breed. Typical symptoms are itching, red skin and secondary bacterial and yeast infections most commonly seen on the ears, face, feet and perianal area, but other areas of the body may be affected.
The third most common type of skin allergy is ATOPY, also known as environmental allergies. As a rule, when your dog comes in with what we suspect is allergic skin disease we will rule out flea allergy first, then food allergy and thirdly ATOPY. Some dogs have more than one type of allergy and present a challenge to diagnose. The best advice when trying to control an itchy skin problem is be patient! It may take a while to get all the problems under control.
There is no quick and easy way to diagnose food allergies. A food trial is required. It can take up to 8 weeks (some specialists recommend 12 weeks) to see maximum improvement from a hypoallergenic diet.
There are many choicesof hypoallergenic diets available. No single diet is the best choice for every patient. One strategy is to start a novel protein diet. A novel protein is one that a dog or cat has never eaten before. Protein in the diet is primarily from the meat source. It is uncommon to see allergies to a protein the body’s immune system has not seen before. Novel protein ingredients may include fish, rabbit, duck, kangaroo, venison, rice, potatoes (sweet and regular) and oats. It is OK to have vitamins, minerals, vegetables and fruit in the diet but NO OTHER protein sources (meat, dairy, or grains). Purina Pro Plan Sensitive Skin and Stomach is a good fish and rice based option. Taste of the Wild, Natural Balance, California Natural, Orijen and Nature’s Domain also make several good options. Be sure to read the ingredient lists as some of the flavors offered by these companies are hypoallergenic (novel protein) but many are not. There are constantly new diets coming on the market so this is just a sampling of what may be available. There are prescription diets available for dogs that still show signs of food allergy on these products. These diets use a different strategy called hydrolyzed protein. In these diets, the protein has been processed by hydrolysis to smaller components that the immune system should not recognize as allergens. Examples of these diets are Hill’s Z/D, Purina HA, and Royal Canin Hydrolyzed Protein.
It is important that your dog eat NOTHING but the hypoallergenic diet during the 8 to 12 week trial period. This includes NO table scraps, treats, rawhide or other edible chew products.
If your dog does not respond to an over-the-counter hypoallergenic diet and we still think it has food allergies, a trial with a prescription diet is recommended. If it is not cost prohibitive for you the initial food trial (12 weeks) is ideally done with one of the prescription diets. A prescription diet is manufactured in a certified allergy free environment on cleaned equipment whereas an OTC diet may contain small amounts of allergens from shared equipment and the environment in the facility.