Itchy dogs: is it allergies?

If your dog is waking you up at night by loudly licking, chewing, and scratching themself, we need to talk. Skin problems are one of the most common reasons pet parents bring their animals to vets (like me). 

While some itching and scratching can be normal, a constantly irritated dog may have something else going on. A lot of pet parents assume it’s allergies — and that could very well be true! But when we say “allergies,” what, exactly, do we mean?

What Actually Is an ‘Allergy’?

An allergy is an inappropriate overreaction of your pet’s immune system to something that would not bother another animal. The immune system in these cases releases compounds that cause itchiness and inflammation, namely histamine and heparin, among others.

Allergies can be a general term to describe a group of clinical signs, such as itchy eyes or a runny nose.

We also use the word allergy to refer to instances when your pet develops hives in response to certain foods, or from touching a certain grass at the park.

More severe allergies can cause such a severe reaction that your dog can start to have trouble breathing or have hazardous drops in blood pressure — a response known as anaphylaxis.

For dogs, allergies most commonly result in itchiness and skin changes rather than symptoms like a cough or runny nose.

Symptoms of Allergies in Dogs

Allergic dogs can manifest symptoms in many ways, some more obvious than others. Many pet parents don’t recognize that their dog is feeling itchy, even when they’re constantly scratching themself. Here are some other signs to look out for:

• Chewing on themselves

• Licking

• Overgrooming

• Hair loss

• Rubbing on surfaces repeatedly

• Head shaking

• Scooting their rear end

• Skin that looks red, inflamed, has pustules, or is hot to the touch

Why is My Dog so Itchy, and What’s Causing Their Allergies?

Now let’s take a look at the three major causes of true underlying allergies in dogs, why skin problems can be frustrating for pets and owners, and what we can do together to manage dog allergies and itchy skin.

Some itching and scratching can be normal. A dog will inevitably need to scratch on occasion, and may be mildly irritated due to certain changes in their environment, even without allergies. But there is a portion of itchy pets that truly do have underlying allergies.

There are three major potential causes of truly allergic pets, which I’ll identify below:

Flea Bites on Dogs

When diagnosing an itchy pet, your vet will want to start by ruling out parasites as the cause. Mites may cause itchiness in pets, and your vet can take a sample of your pet's skin to make sure there aren't any mites present.

Fleas are the major parasite responsible for allergic reactions in pets. They can irritate any animal, but some pets are actually allergic to flea saliva. This means their immune system releases compounds that cause itchiness and inflammation in response to flea bites, which can cause major hair loss, redness, skin infections, etc. We refer to this as flea allergy dermatitis, or FAD.

My first step when working on an itchy pet is to make sure they are already on regular flea prevention, so we can take fleas out of the equation. It may be safe to start puppies on preventative flea-and-tick medication as early as 5-6 weeks of age, but most products on the market are licensed for use in pets over 8 weeks old — right around the time they’re getting their first vaccinations. The safe minimum age will vary by product, so it’s important to read the drug handout and check with your vet. (Most responsible breeders won’t let you bring a dog home before they’re at least eight weeks old.) 

So whether you’re purchasing a new puppy or adopting an older shelter dog, you should be able to start administering flea and tick meds as soon as you bring your dog home.

Food Allergies in Dogs

A lot of owners quickly jump to food as the cause of allergies in their dog. This could be true, though truly food-allergic pets are not our most common itchy animals.

While many people believe that food allergies are caused by grain, the real inflammation-causing culprit in the majority of food-allergic pets is the diet’s protein source. This means chicken, turkey, beef, venison, duck, dairy etc. It’s true that some animals can be sensitive to things like wheat or corn, but most of our true food sensitive pets are reactive to the protein.

The only way we can determine whether a pet is food allergic is to perform what’s called an “elimination diet trial” with a novel protein or hydrolyzed protein diet.

A “novel protein” refers to a protein source the pet has never had before, and a hydrolyzed protein is a protein source that has been made to be very broken down so it is less likely to stimulate the immune system. Today, even more sources of protein are being considered for use in allergic pets, including plant- or insect-based proteins. Any of these may be used to see if we can decrease the reactivity from the immune system.

Diet trials can be challenging for owners because the pet has to eat only the diet trial food for upwards of eight to 12 weeks, so everyone has to be dedicated to sticking to it. At the end of that time period, we assess the pet’s symptoms. If we see an improvement in itchiness we can then challenge the diet by adding back in one new thing at a time to see if the itchiness worsens or recurs.

This helps us plan out what the pet can safely eat in the long term without experiencing severe allergic symptoms.

Yes, there are blood tests that check for food allergies, but unfortunately these are not very accurate.

Food

A lot of owners jump to food as the cause of allergies in their pets. This could be true, though truly food allergic pets are not our most common itchy animals.

While many people believe that food allergies are caused by grain, the real culprit of causing inflammation in food allergic pets is the diet’s protein source. This means chicken, turkey, beef, venison, duck, etc. It’s true that some animals can be sensitive to things like wheat or corn, but the majority of our true food sensitive pets are reactive to the protein.

The only way we can determine if a pet is food allergic, is to do what’s called a diet trial with a novel protein or hydrolysed protein diet.

A novel protein is a protein source the pet has never had before and a hydrolysed protein is a protein source that has been made to be very broken down so it is less likely to stimulate the immune system.

Diet trials can be challenging for owners because the pet has to eat only the diet trial food for upwards of eight to 12 weeks, so everyone has to be dedicated to sticking to it. At the end of that time period we assess the pets symptoms, and also challenge the diet by adding back in one new thing at a time to see if the itchiness worsens or recurs.

This helps us plan what the pet can eat long term safely without causing severe symptoms.

Yes, there are blood tests that check for food allergies, but unfortunately these are not super accurate.

Environmental Allergies

Your dog may be sensitive to that big beautiful world out there. Possible allergens include things like grasses, pollens, dander, or dust.

In addition to trying to avoid things you know your dog is sensitive to, there are lots of medications available that can help manage symptoms of an allergic pet. These include both topical treatments like creams or shampoos, as well as oral or injectable medications. Chatting with your vet can help determine what regimen works best.

A blood test can be performed to determine what types of environmental allergens are an issue for your dog.

That being said, the most accurate way to determine what allergens are bothersome is to conduct intradermal skin testing at the veterinary dermatologist. These clinics perform testing just like in humans to grade your dog’s reaction to common allergens.

The end goal of allergy testing (whether that be by blood or the intradermal test) is to formulate allergy immunotherapy specific to your dog. This can be in the form of injections, or an oral liquid given under the tongue to help slowly desensitize your pet to the things that are causing their symptoms.

Can Dog Allergies Be Cured?

Vets see lots of clients who express frustration with the fact that their allergy-suffering pets need so many repeat trips to the clinic. I completely understand this frustration, as I have a dog with allergies at home.

An important concept vets like to relay to pet owners is that we cannot CUREallergies in pets, but our goal is to decrease the number of flare-ups they experience and make those symptoms less severe when they do happen.

Dogs also commonly develop secondary bacterial or yeast infections which require treatment. This means we have to make sure we’re taking care of the primary issue (itching) and the secondary issues (infections) to have success.

Allergies are a condition that gets managed over time rather than a ‘one and done’ treatment type scenario. Because of this, it’s important that dog parents understand that finding a regimen that works for your furry friend can take some time and some tweaking. But doing so will help you and your dog in the long run.

When to See Your Vet for Dog Allergies

If you notice any of the above signs of itching in your pet, it may be time to call your vet.

In particular, if these lead to redness, hair loss, or skin lesions, it’s time to take a trip to your vet to get your pup examined — and to formulate a plan. This is absolutely true if your pet is a repeat offender, as we definitely become more suspicious of an underlying allergy in those cases!

How Can I Help my Dog’s Allergies?

While truly allergic dogs will likely need long-term support from your vet, there are some things pet owners can do to help.

Keep your pet on regular parasite prevention (monthly, all year round). And if your vet has prescribed medication to help treat your pet’s skin, finish the entire course of medication, even if the symptoms get better before the end of therapy. 

If you can, avoid allergens that you know your pet is sensitive to (e.g. certain grasses, pollens, dander). And contact your vet for help before symptoms get severe. If secondary infections are present, they can be easier to get rid of the sooner your vet can address them. 

Finally, you can ask your vet if supplements can help with inflammation. Or you can ask if they’ll recommend any other home remedy for a dog with itchy skin. Safe natural remedies that your vet might recommend include something like omega 3 fatty acids.These supplements, which you can administer orally or topically, may help combat itchiness and dry skin. Just make sure you apply a supplement that’s formulated specifically for dogs, not for humans.

Preventative routines may also include effective veterinary topical therapies such as ear cleansers, skin mousses/wipes, or shampoos. There are several products on the market — which can get confusing for owners — so chatting with your vet can help weed out some of the less effective options. 

Veterinarians and veterinary dermatologists tend to lean towards products with ingredients that will help rebuild and maintain a healthy skin barrier, or even prevent buildup of problematic debris. These products might include ingredients like phytosphingosine, Ophytrium, or N-acetylcysteine. Promoting a healthy skin barrier may help your pet react less to allergens that would normally stimulate severe inflammation. 

Just remember, you should never administer any treatment for your dog’s itchy skin without consulting a vet first. 

If you need ongoing medication to soothe your pet's allergies, check if an online pharmacy might be able to dispense your prescription. This medicine is often delivered quickly, and it can be more affordable in the long run.

There are so many ways to keep your itchy dog comfortable now. Work with your vet to come up with a management plan, and be vigilant about any changes in your pet’s symptoms so you can act fast to stop things from escalating.

Does Pet Insurance Cover Allergies?

If your dog suffers from allergies, you may need to manage their flare-ups throughout their life. This can get very expensive — lots of pet parents with allergy-afflicted dogs need to claim several times a year! But if you’ve already purchased dog insurance before their allergy symptoms manifest, your policy may help cover the cost.

Ultimately, pet insurance for a dog with allergies may be a huge financial help — but only if your dog is insured BEFORE they become symptomatic. If a chronic condition arises before your pup is insured, it likely will be excluded from coverage as a pre-existing condition. 

That’s why it’s so important to purchase insurance for your dog when they’re still young.