By Joe Spoo DVM

One of the more frustrating cases we see in veterinary medicine is the case of an itchy dog—those dogs that are constantly battling skin infections, ear infections, or are just plain miserably itchy. There are a number of things that can make a dog itchy, from bugs to behavior, but this article is going to address dogs with allergies—those dogs that seem incredibly itchy all the time or every year seem to get the same skin and ear infections.

ALLERGIES IN A NUTSHELL

When you or I think of allergies in ourselves we think of things like hay-fever, asthma, sinus problems, etc. The same irritants that cause allergies in us can cause them in our pets. The difference is dogs get itchy and irritable skin instead of respiratory problems. Dogs with allergies to food will show their symptoms through itchy skin. Where this problem becomes even more of an annoyance is when this already irritated skin becomes infected, which I’ll discuss later.

Basically there are two types of allergies in dogs. The first type is inhalant, with allergies to various pollens, dusts (both outdoor and indoor), dander, etc. These dogs are typically itchy seasonally, and you can practically set your calendar by various bouts with ear infections, hotspots or excessive itching. The other type of allergy is food allergy. Some dogs can develop an intestinal irritation or allergy to food, but an even larger group will develop an allergy to some component of the food that will show up as itchy, irritable skin.

The most important thing to understand as an owner of an itchy dog is that this is a condition that will only be managed and likely never be completely resolved. It is also extremely important to stay in touch with your veterinarian about the success, or lack thereof, of treatment protocols. During the initial stages you may need to schedule rechecks every 2-3 weeks to ensure infections are controlled and the symptoms are in check. Likely you have a dog that will either need some type of treatment for a large portion of the year or potentially a prescription diet for the rest of its life. Too frequently we want to give a shot or a pill and have the problem go away, unfortunately with allergies that doesn’t happen. Think about how many people, young and old, take at least some type of medication daily? Why should we not expect the same to occasionally occur in our pets?

ALLERGY DIAGNOSIS AND TREATMENT

The first place I start with these itchy dogs is to determine if there are any secondary infections (i.e. ears, feet, skin), usually bacteria and/or yeast, and to diagnose and treat these before addressing the allergies. If you were going to rate an allergy dog on a scale of itchiness of 1 to 10, and let’s say your dog scores a 6, the same dog with secondary infections may be an 8, 9, or 10. Often times these infections are treated for 2-3 weeks with some combination of antibiotics, anti-fungals, and medicated shampoos. Depending on the individual case I will either begin management of the allergies in conjunction with the treatment of these infections or immediately following.

With inhalant allergies there are numerous paths and medications for treatment, but unfortunately it can be a long, frustrating problem to find the right combination of products to keep these dogs from becoming miserable. The important key here is to continue communicating with your veterinarian about what treatments are working and those that are not. Although frustrating, it is possible, with some work from the veterinarian and owner, to make these dogs have much more comfortable lives.

THE TRUTH ABOUT FOOD ALLERGIES

Many people jump to the conclusion that their dog is itchy as a result of the food they are feeding, when in most cases this just isn’t the case. Of all the allergies dogs experience only 10% are triggered by food. Of this 10%, 80% are allergies to beef and diary, and a majority of the remainder is to the protein source in the food.1 I believe that food is often incriminated because many dogs are fed a very low-quality food and when switched to a prescription diet or a novel diet the dog’s skin improved. And while it would appear that the problem was food-related many of these dogs would have benefited from feeding a higher-quality food and may not have had to jump all the way to a prescription-allergy diet.

Corn and wheat are two products that get a bad reputation in dog food, and often undeserved. When used for their good qualities they are an exceptional ingredient in pet foods. The cause for the bad reputation arises in some lower-end products when there is a large amount of both or either of these products, to the point they become somewhat of a filler. Often the source of the problem is that the food is of a lower quality, and not that either of these ingredients is triggering a problem. They are not any more likely to trigger food allergies than any other particular ingredient, and it is important to separate fact from internet lore when evaluating foods. Great care goes into the selection of the proteins and carbohydrates used in most premium pet foods (see sidebar). While food may be a component in why your dog is itching, the odds are greater that it is not the inciting cause.

Every system in the body can suffer from poor nutrition and likewise can benefit from premium nutrition; this is also true of the skin. Premium foods supply your dog with the basic building blocks for healthy skin. Dogs receiving poor levels of a poor quality protein will show evidence of greasy, scaly skin with a dry brittle hair coat. In addition to high-quality proteins, premium foods will provide the correct balance of Omega 6 & 3 fatty acids, which have been shown to aid in overall skin health, and incidentally, will also benefit dogs with inhalant allergies. Certain mineral deficiencies, zinc for instance, can also lead to problems with the skin and hair coat. For this reason, most premium diets contain high-quality sources of minerals to ensure dogs are getting adequate amounts.

No matter the cause of the itching, I like to get these itchy dogs on a high-quality diet, because even if it does not eliminate the problem it will greatly benefit the dog overall.

If the problem is a food allergy, the dog will need to undergo a diet trial of 6-8 weeks. During this trial the dog will only be able to eat the prescribed diet—no treats, rawhides, or tablescraps. I also would strongly encourage sticking with a veterinary diet, as many over-the-counter diets contain similar ingredients to one another, and although the bag may claim to be for sensitive skin, if the dog is truly food allergic it may not help in the least. If the diet trial is successful and the itchiness resolved you can begin to add back in, one at a time, some of the treats, chew toys and possibly food the dog had been using previously in order to determine the trigger of the allergies.

Unfortunately there usually is no quick cure for the itchy dog. Rather it is a process of finding out what is causing the itching and another process of trying to find the correct combination of things to help stop the itching. If not on a premium product an itchy dog definitely would benefit from an improvement in food quality; it is just important to remember this may not be the only change that will be needed.

Sources:

1. Iowa Veterinary Medical Association Winter Conference. Feb. 9. 2005. Approach to Pruritic Dermatitis; Keith A. Hnilica DVM, MS Diplomat ACVD.
2. Case LP, et al. Nutritionally Responsive Dermatoses in Canine and Feline Nutrition. Second Edition, St. Louis, MO, Mosby, 2000.