Itchy skin in dogs is common and not always easy to resolve. No wonder there are internet-driven “quick fixes”: People want to help their pets as quickly and easily as possible. It can be tempting to fall for any plausible idea.
The “raw food” phenomenon is a good example of this. There are anecdotes of itchy dogs switching from a commercial diet to a raw meat diet resulting in an instant resolution of the itch. As a veterinarian and a scientist, I am interested in such case histories, but I also want to explain the science behind them.
Itchy skin does not occur spontaneously: The itchiness always has an underlying cause, which is referred to as the “main cause”. A veterinarian’s goal is to identify this cause and then remove it from the dog’s life or use medication to minimize the itching.
Food allergy is why around 20% of itchy dogs develop a skin condition. So, if you change their diet, there is a good chance that 1 in 5 dogs itchy will cure the itch. This is the reason behind these anecdotal cases of raw food releasing itchy skin. The other side of this data is just as important: in 80% of dogs that itchy, changing their diet does not help.
It’s also important to keep in mind that a raw diet isn’t the only possible answer in such cases. In dogs that are allergic to food, the itchy skin is the result of an allergic reaction to a certain component of the food, most often to a protein. Studies show that the most common food ingredients that cause allergic reactions are beef (34%), chicken (17%), lamb (15%) and wheat (14%). So, if you remove just these four ingredients from your allergic pet’s diet, you have an 80% chance of stopping the problem. In those cases where a raw food diet helps, it is because a specific protein is being used (e.g. turkey) and your dog is not allergic to that protein.
When vets investigate a food allergy as a possible cause of itching, they tend to take a different approach: instead of suggesting a raw diet, they usually recommend a so-called “hydrolyzed” diet. This is a commercial diet that has been pre-digested so that it no longer contains protein chains long enough to cause an allergic reaction. This is more likely to be successful than a raw food diet, as itching is almost guaranteed to prevent itching in all food-allergic dogs because it does not contain any allergens. Usually an attempt of 6 – 8 weeks is sufficient: If your dog stops itching during this time, the cause is in fact a food allergy. If you continue to experience itching despite following the special diet, it is very unlikely that a food allergy is the cause.
In addition to the fact that hydrolyzed diets are the gold standard in diagnosing food allergies, veterinarians also have reservations about raw foods in general: raw meat often contains bacteria that can be dangerous to humans, and these bacteria can spread widely around the home. Coats and bowls of dogs. When people in the household are at risk (such as young children, the elderly, or those receiving chemotherapy), there is a significant risk of health problems related to the bacteria from raw meat. This can be a risk that can be successfully managed, but it is important to be aware of it.
It is also important to remember that 80% of itchy dogs do not have a food allergy: changing their diet will not help these animals. Other common causes of itchy skin are external parasites (such as fleas and mange), allergies to dust and pollen (so-called “atopic dermatitis”) as well as direct contact irritation and allergies (e.g. caused by sensitivity to grass or vegetation). Often times, the initial primary cause of the itching is complicated by a subsequent secondary infection of the damaged skin with yeast and bacteria. Even if the original cause is removed, these infections can keep a dog itchy if not treated properly. Because of this, a visit to the vet is probably the quickest solution for your pet.
Aside from food allergies, diet continues to play a general role in skin diseases in dogs: daily supplementation with omega-3 fatty acids (such as mackerel oil) can support the skin’s barrier function, reduce the effects of allergies and reduce the risk of secondary complications such as bacterial and Yeast infections. Regular shampooing can also help itchy dogs in general by using a product designed for use on dogs (human skin and hair have a different pH than the dog equivalent).
The good news is that most itchy dogs get better within three visits to the vet, although in some cases life-long anti-inflammatory medication is required. On rare occasions, some obscure cases may need to be referred to veterinary skin specialists (such as Skinvet Ireland of Cork – www.skinvet.ie).
Last week I mentioned new treatments for arthritis in pets: Similar advances have been made in treating allergic skin conditions. Traditional anti-inflammatory drugs like prednisolone tablets can have significant side effects with long-term use, and a newer veterinary pharmacy supplement, ciclosporin, may be more effective. Drugs that inhibit certain inflammatory biochemicals have recently been introduced: the latest is a once-monthly injection of monoclonal antibodies that targets these “itchy” molecules in your dog’s body and supports allergic skin conditions with minimal side effects.
Raw meat diets have their place, but they’re not a panacea for dogs with itchy skin.