Your dog is itching like crazy, constantly shaking its head and scratching its ears non-stop.
Your mind might jump straight to flea allergy dermatitis or something triggered by any number of potential environmental allergens – but that's not always the case.
What else could be the cause, then?
Well, dog food allergy is another potential cause to consider – and to make matters worse, the symptoms of different types of allergies can often overlap.
As in, they can be almost identical.
So, don't jump to conclusions.
Learn more about food allergies in dogs – starting with this guide – and go from there!
Dog Food Allergy Vs. Intolerance: Understanding The Difference
Adverse food reactions are defined as abnormal – or in any way unexpected – responses to a food or a particular ingredient in it.
Much like their favorite humans, dogs can have negative reactions to certain foods – and, more specifically, ingredients in those foods. But these adverse food reactions aren't always the result of a dog food allergy.
Sometimes, food intolerance is to blame.
What's the difference, you ask?
Adverse food reactions in dogs are often labeled as "food allergies" – although that's not entirely accurate.
They can be caused by food intolerance or an actual food allergy. The main difference between the two is the immune system trigger:
Both may lead to an adverse reaction – but food intolerance doesn't involve your dog's immune system; the response is purely non-immunologic. When there is an immune component causing an abnormal reaction to "normal" food, the adverse food reaction is considered a real dog food allergy.
To put it simply:
Allergic reactions happen when the immune system mistakes a particular substance – in this case, a dog food ingredient – as an invasive threat to the body. Your dog’s immune system will respond to that threat by launching an attack and creating antibodies to fight off the invading enemy.
Here's a bit of good news:
Only one in ten dogs who display adverse food reaction symptoms turn out to have an actual dog food allergy.
That's not to say that pet parents should dismiss their dog's symptoms as "nothing too serious." But as I said earlier, it's best not to jump to conclusions.
Food Allergy Testing & Elimination Diet: How Do You Know If It’s A Dog Food Allergy?
If you think that your pooch might be suffering from a food allergy, talking to your vet and trying to find the exact allergen causing the symptoms should be the first thing you do.
Your veterinarian will start by ruling out any other conditions that might be causing your dog's symptoms. Once they’ve narrowed it down to dog food allergy as the probable cause, they may propose an elimination diet as a way of diagnosing your dog.
Why not an allergy test, you ask?
If you've ever undergone allergy testing of any kind, then you're probably aware that diagnosing allergies is often much more complicated than it seems.
The same is true for your pup.
Dietary elimination trial – known as the elimination diet – is the golden standard for diagnosing a food allergy in dogs. However, the process can take up to 12 weeks – or longer in some cases – and requires a lot of commitment, vigilance, and strict supervision over your dog's diet.
Many pet parents will have a hard time making sure that the dog's diet is entirely compliant with a dietary elimination trial's strict rules for months.
That's why it's best to combine the elimination diet with an at-home allergy test kit.
It's the most reliable way to identify the exact ingredients that are triggering your dog's allergic reaction. There are commercially available allergy test kits you can do at home to "confirm" the elimination diet's findings further.
In case you're interested, you can check out the best dog allergy test kits right here.
Dog Food Allergy Symptoms: What Are The Signs Of A Food Allergy In Dogs?
Dog food allergy symptoms can be wide and varied – from gastrointestinal symptoms such as vomiting and diarrhea to chronic ear infections and dermatological symptoms.
But here's where things get confusing for most pet parents:
Food sensitivities, real food allergies, and allergic reactions caused by environmental allergens can often result in similar – almost identical – symptoms, making it hard to get to the root of the problem.
Generally speaking, though, if your dog has a food allergy, you may notice some of the following symptoms:
- Itchy skin coupled with non-stop scratching – a condition called allergic dermatitis –can affect any part of your dog's body but often occurs around the ears, paws, rear end, and stomach.
- Skin irritation and rashes, including hives – a skin condition known as urticaria – with itchy red bumps typically appear within 24 hours after coming in direct contact with the allergens in food. If your pup has short hair, the hives will be easy to spot, and you might notice that your dog is scratching, biting, or licking those areas, which could lead to skin infections and hair loss.
- Itchy paws, accompanied by excessive licking, biting, and discoloration.
- Chronic ear infections, which could indicate food allergies as well as food sensitivities in dogs.
- Gastrointestinal problems, including vomiting, diarrhea, and gas – although digestive issues often point to food sensitivity, rather than a true food allergy. Only 10% to 30% of dogs diagnosed with food allergies will display GI symptoms.
- A swollen face, and more specifically, swelling that occurs on your dog's lips, ear flaps, and eyelids.
- Red eyes, often accompanied by discharge.
- Hair loss, commonly a result of excessive scratching and other skin-related symptoms.
- Secondary yeast or bacterial infections – known as pyoderma – that's secondary to allergic dermatitis and affect the skin's surface due to scratching.
Behavioral changes are rare but can occur as secondary to or linked to the discomfort caused by the symptoms discussed above.
You may notice:
- Frequent rubbing against the furniture, your legs, and other "scratchy" surfaces
- Constant shaking of the head
- Biting at the paws and tail
- Reduced interest in playtime and general withdrawal
- Anorexia and sudden disinterest in food
Here's what to keep in mind:
Vomiting, diarrhea, and other gastrointestinal symptoms are far more likely to be caused by food sensitivities than food allergies.
On the other hand, dermatological symptoms that can manifest as itchiness, irritation, and hives seem like a reaction to environmental allergens and flea bites. But these symptoms, more often than not, point to a dog food allergy.
Do you see how confusing it can get?
It's best to monitor your dog's symptoms closely and then work with your veterinarian to figure out the root cause.
Most Common Dog Food Allergens To Watch Out For
It's important to remember that the longer the dog's exposure to a specific food, the more likely they are to develop food sensitivity – or an actual food allergy.
That's one of the reasons why sticking to the same dog food for months – or years – at a time is generally a bad idea.
Carbohydrates are less likely to cause an allergic reaction; grain-free diets can contain just as many food allergens as any standard dog food recipe.
Preservatives, additives, and artificial coloring are also unlikely to cause a food allergy. But it's generally a good idea to stay away from dog foods that include these ingredients since they're known to lead to other adverse reactions.
That leaves us with proteins as the nutrient most commonly associated with allergies in dogs.
Meat, eggs, and dairy are generally considered the most common dog food allergens. Keep in mind that the proteins found in these foods – and not the food itself – lead to adverse reactions.
Dog Allergy To Beef
Protein is the most common food allergen – and beef is leading the way as the most common one of all.
You see, beef is a frequently used ingredient in pet foods – and the more common the food, the higher the risk of a dog allergy to beef. With that in mind, you shouldn't be surprised to find that more than 30% of food allergies in dogs are traced back to beef proteins.
So, let me ask you:
Have you been feeding your pup the same commercial dog food for years – and does it list beef as one of the main ingredients?
If the answer's "Yes" and your dog is exhibiting recurring skin or gut issues as of late, then yes, there's a pretty good chance that they developed a dog allergy to beef.
Dog Allergy To Chicken
This fact might surprise many pet parents out there, but dog allergy to chicken is the third most commonly reported food allergy in dogs.
But it's plain, old chicken – how could it ever be an issue?
As I said earlier, protein sources most prevalent in commercial dog foods are also most likely to trigger the immune system's response.
Beef aside, chicken is one of the most popular proteins found in dog foods – from kibble and wet food to treats. As a result, there's a higher chance of your dog's immune system becoming overly sensitive to something as simple as chicken.
Dog Allergy To Fish
For your dog to become allergic to a specific protein, they have to be exposed to it. And as you can imagine, many dogs are not fed strictly seafood – or, more specifically, fish.
That's not to say that a dog allergy to fish isn't a possibility; it certainly is.
However, reports of fish allergy in dogs are rare and far between – only about 2% of dogs suffer from an allergy to fish or seafood in general. If your dog's diet contains fish, though, and they’re showing allergy-like symptoms, be sure to mention it to your veterinarian.
Dog Allergy To Lamb
Lamb was once the go-to animal protein in hypoallergenic dog food, primarily because beef and chicken are more common in commercially available foods – and, in turn, more likely to turn into allergens.
However, that doesn't mean that your dog can't develop a food allergy to lamb – especially now that it's become more commercially available.
If your dog shows signs of extreme itchiness, excessive licking, skin changes, or is exhibiting GI symptoms, do not hesitate to contact your vet.
Dog Allergy To Eggs
Raw eggs are a terrible idea in general – whether they're allergic or not – as they could expose your dog to salmonella. I wanted to make that clear before talking about egg allergies in dogs.
Your dog's immune system can overreact to the proteins found in the egg yolk, although egg whites – and the shell itself – can trigger an allergic reaction, as well.
It's easy to avoid eggs, though – as long as you double-check the food labels for ingredients such as:
- Whole egg
- Egg wash
- Dried egg
- Powdered eggs
Dog Allergy To Wheat
There are many misconceptions among dog owners regarding food that contains carbohydrates – and more specifically, grains. Grain-free dog food has become one of the hottest fads among pet parents in recent years, which proves my point further.
Dog allergy to wheat is far less common than an allergy to beef, for example – but there's still a possibility that your dog has an adverse reaction to wheat. Itchy, inflamed skin, discoloration of the paws, and chronic ear infections are common symptoms.
If you notice digestive issues – such as bloating, diarrhea, and gas – maybe gluten sensitivity is to blame.
Every dog's diet requirements are different, though. Don't cut out grains, including wheat, out of their diet until you've talked to your vet.
Dog Allergy To Dairy Products
Many dogs are lactose intolerant and have a hard time digesting milk and other dairy products.
But that's food intolerance – not an actual allergy.
That brings me to my next point:
Dairy – or, more specifically, the protein found in milk – is one of the most commonly reported allergies in dogs, second only to beef.
When you're trying to determine if your pup is suffering from a dog allergy to dairy products or mere lactose intolerance, watch out for the symptoms:
Lactose intolerance commonly manifests as GI symptoms, such as vomiting, diarrhea, and gas, while a dairy allergy typically causes itchiness and other skin-related symptoms.
Dog Allergy To Soy
When it comes to dog allergy to soy, I'm afraid there are a lot of "maybes" and not enough solid proof.
Yes, soy protein is a recognized allergen for dogs. Then again, there are instances where soy can be beneficial for dogs with other dietary sensitivities and allergies.
To add to the confusion, certain studies indicate that excessive consumption of soy can lead to other health issues, besides just food allergies. So, maybe you should reconsider including it in your dog's diet – even if they're not allergic.
That mostly depends on your dog's stage of life and existing medical conditions, though.
Dog Allergy To Corn
Generally speaking, food allergies in dogs are most often caused by a protein in your dog's diet. However, some pups can be allergic to corn – a common ingredient in many dog food recipes.
It will present itself as any other dog food allergy, with the leading symptoms being skin irritation and itchiness, hives, and in some cases, GI symptoms.
The good news is that dog allergy to corn is less common than most pet parents would assume; reports suggest that only about 4% of dogs with diagnosed food allergies are, in fact, allergic to corn and corn-based products.
Dog Allergy Treatment: How Is A Food Allergy In Dogs Treated?
Now that you've pinpointed the exact offending items in your dog's diet, the hard part's over – or is it?
There's no real "cure" – not in a way that would make the allergy go away permanently. Treating a food allergy in dogs is generally a matter of avoiding the allergens as much as possible.
So, given that avoidance is the only actual dog allergy treatment, a hypoallergenic diet – as in, a diet that doesn't contain any of the allergens – is your dog's best bet.
You can go with a vet-prescribed diet, home-cooked dog food, or a limited-ingredient diet. Either way, a different set of ingredients should be enough to improve the symptoms and avoid further reactions.
Aside from that, your vet might recommend antihistamines and topical anti-itch ointments as a way to relieve some of the symptoms.
But generally speaking, treatment options are something that you should discuss with your vet. While you're at it, ask them to recommend the best dog foods for your pup's allergies – I'm sure they'll be happy to help you figure this whole dog food allergy thing out!
Dog Food Allergy: Conclusion
Caring for a dog with a food allergy might seem challenging – and, at times, even disheartening. But with a bit of care and education on the matter, it's entirely possible to give your beloved pup a long, happy, and healthy life.
Yes, many dogs will have to stick to a special diet for life due to the dog food allergy – but you shouldn't let that discourage you.
There are so many commercially available foods on the market and various animal proteins and grains to choose from when putting together a hypoallergenic diet for your dog. Finding the right solution to your dog's symptoms shouldn't be too hard.
So, if you have a dog with food allergies, remember – it will get better!