Dermatitis in dogs

Written by Pure Pet FoodPure Pet Food are the experts in healthy dog food and healthy dogs featured in media outlets such as BBC, Good Housekeeping and The Telegraph. Working with high profile veterinary professionals and nutritionists, Pure Pet Food are changing dog food for the better. Dr Andrew Miller MRCVSDr Andrew Miller MRCVS is an expert veterinary working in the field for over 10 years after graduating from Bristol University. Andy fact checks and writes for Pure Pet Food while also working as a full time veterinarian. - Our editorial process

Characterised as an itchy and incredibly irritating skin condition, canine dermatitis essentially refers to an allergy which causes sore, inflamed skin. Just like humans, our dogs can be allergic to various substances, and these substances are usually the ones that dogs commonly encounter in their everyday life.

Dermatitis is a very common medical complaint in both humans and dogs and although it doesn’t have any severe implications, it can cause your dog extreme discomfort and pain.

What is dermatitis in dogs?

Causing major irritation and inflammation, dermatitis is a common skin allergy that can impact any breed at any age. Similar to eczema and pyoderma, dermatitis will isn't life-threatening, but it can sure cause them a lot of pain and annoyance. Despite this, most dogs develop allergies at a young age, so you’re likely to notice the onset of dermatitis when your pup is a youngster.

Dermatitis can be differentiated into two types, parasitic/flea allergy dermatitis and atopic dermatitis.

Parasitic dermatitis is triggered by an allergic reaction to a parasite, whereas atopic dermatitis is much broader, referring to an allergy to airborne or ingested substances such as pollen.

Dermatitis or pyoderma?

Dogs can suffer from several skin disorders, making it easy to confuse the various types. Pyoderma is one that looks a lot like dermatitis, both showing in a red rash on the skin.

However, dermatitis is a skin condition that predisposes dogs to pyoderma, which is a skin infection. Pyoderma can be distinguished from dermatitis as the rash forms in red raised pimples with a white pus-filled centre.

Discover delicious food your dog deserves

Learn more

What causes dermatitis in dogs?

Primarily, dermatitis is caused by an allergic reaction to harmless, innocent things that we encounter in everyday life. At the moment, it’s uncertain why some dogs are allergic to certain triggers.

However, the current thought is that some dogs are genetically predisposed to allergies. Dogs that suffer with dermatitis will often have flare-ups caused by multiple triggers. Some of the most common triggers include:

Environmental allergies

Dogs, just like us, can be allergic to things in the air, such as pollen, grass, dust and mould.

Reactions to environmental factors such as pesky pollen and grass can often be attributed to hay fever season. It might come as a surprise, but our pooches can actually get hay fever too!

Food allergies

Most dogs like to wolf down any type of food, whether that be their own dog food or food they’ve stolen from your plate! Unlike people, most dogs don’t really turn down food, even if they know it makes them poorly.

Food allergies are surprisingly really common in the canine world, which many people probably wouldn’t expect. Many dogs aren’t exactly picky with what they eat.

It could come as a shock, especially if you’ve fed your pup the same food for their entire life and they’ve only just started having a reaction. However, allergies can occur at any time. Food allergies will often show through dermatitis and an upset stomach.


Parasites such as fleas, ticks and mites are troublesome and will impact almost every dog at some point in their life. In general, a parasite will always be irritating, but some dogs can actually encounter an allergic reaction, leading to parasitic dermatitis.

Typically, your pooch won’t be allergic to the parasite itself, but rather the structure of the parasite’s saliva. If your dog does experience parasitic dermatitis, they’ll have a reaction each time they get bitten.

Where does dermatitis usually show on dogs?

The skin irritation can sometimes be concentrated in just one primary area on a dog’s body, or it could affect their entire body. Most commonly, dermatitis appears in these main areas:

  • Ears

  • Paws

  • Tummy

  • Armpits

  • Groin

What are the signs and symptoms of dermatitis in dogs?

Predominantly, dermatitis shows itself through irritated skin, but this could lead to your pooch displaying strange behaviours. The main symptoms of canine dermatitis are:

  • Itching/excessive scratching

  • Rubbing on carpet

  • Hair loss or thinned hair on affected area

  • Greasy or flaky skin, odour

  • Chewing paws

  • Saliva staining (red/brown staining on the fur where your dog has been licking)

  • Redness/rashes, especially on the belly

  • Spots and crusting

  • Ear or skin infections

Are some dogs more likely to get dermatitis?

It’s agreed that some breeds are more genetically predisposed to developing allergies and dermatitis than others, for instance, Golden Retrievers, Cocker Spaniels, Boxers, Bulldogs, West Highland White Terriers and Shih Tzus.

Despite this, any dog breed can suffer from dermatitis, including mixed breeds. Dogs of all ages can also suffer with the condition, but it’s most likely to appear when your dog is young and continue flaring up throughout their adult years.

How is dermatitis in dogs diagnosed?

As dermatitis is essentially just a broad term to refer to skin irritation and inflammation, your dog can be easily diagnosed by your vet just from the appearance of the reaction. However, diagnosing what is causing your dog to have dermatitis is the crucial and tricky part of the process.

Many dogs who suffer from dermatitis are allergic to several different substances. It might also seem that your dog experiences the symptoms of dermatitis sporadically, meaning an exact trigger will be difficult to pinpoint.

If your pup is having symptoms of the condition, your vet will be able to conduct various tests to potentially detect the exact allergy/allergies causing dermatitis. Prior to carrying out any tests, your vet will need to eliminate if the dermatitis is caused by fleas as this can be easily treated by eliminating the parasites.

Alongside this, it must be worked out if your pooch is allergic to their food. Food trials can be performed if the condition is suspected to be caused by a food allergy. This involves giving your dog nothing but a specially formulated food that they definitely won’t be allergic to for a number of weeks. Take notes on how your dog reacts and how the dermatitis changes day by day.

If the dermatitis symptoms subside or completely go away, it’s extremely likely that they were allergic to something in their current food. However, if the problem remains the same, it means their allergic reaction must stem from elsewhere. Keep in mind that if your pup eats one thing that transgresses from their specialised diet, they might react so the process will need to be started from scratch.

Once the vet has confirmed that your pooch isn’t suffering from any allergies to fleas or their food, they can carry out specific allergy testing.

Allergy testing

Serological allergy testing is a possibility, which involves taking a blood sample and identifying which specific substances are instigating the allergic reaction. Unfortunately, this method of testing has led to many unreliable results.

Intradermal testing is another method of determining what’s instigating the allergic reaction. This procedure involves injecting your dog with incredibly tiny amounts of the suspected allergens to test if your dog reacts to them.

Your vet will note if your dog develops any kind of redness, inflammation, or bumpy skin (wheals), which will confirm if your dog is allergic to that substance. Don’t worry, your vet won’t use a test amount that’ll cause your dog to have a severe reaction.

How is dermatitis in dogs treated?

Dermatitis isn’t fully treatable as you can’t prevent your pooch from having allergies. However, the skin condition can be managed exceptionally well to the point where your dog rarely experiences dermatitis, only getting flare ups occasionally.

As stated, dermatitis can be provoked by many different triggers, with some dogs even experiencing it due to multiple allergies. As a result, there are several different treatment options available to cater for all the varying triggers. Discuss this with your vet to determine the optimum treatment plan for your pooch.


Antihistamines can be supplied by your vet to minimise the allergic reaction your dog has to the trigger. Success rates vary with antihistamines, some owners experience a significant improvement in their dog’s dermatitis whereas some see little to no difference.

It’s highly important that you never provide your dog with antihistamines that you just have at home. Although some human antihistamines are safe for canine consumption, it’s very risky to give your dog medication that hasn’t been supplied by your vet.

The tablets could potentially be dangerous to dogs, or you could give your dog the wrong amount of medication for their size, putting them at extreme risk.


Medication provided by your vet can have a considerable improvement on your dog’s itchiness and inflammation. However, steroids will likely only be provided for a short period of time as they can have long term side effects.

Flea treatment

Keeping up to date with flea treatment is essential if your dog has been diagnosed with dermatitis due to a flea bite. Your vet will provide you with the appropriate treatment to resolve the issue by killing the parasites and soothing inflammation and itchiness.

Medicated shampoo

Your vet may recommend a medicated shampoo to wash your dog with. The shampoo will contain the correct ingredients to hopefully calm your dog’s skin, ease the itchiness and reduce any redness.

If your pooch suffers from allergic dermatitis, especially from substances that occupy the air, giving your dog regular baths anyway are a great way to eradicate any allergens residing in their fur.


Immunotherapy is the process of your vet giving your dog several, small injections of the allergen that causes the flare-ups of dermatitis.

This is a process that will happen slowly over time, but in the end, your dog should have built up an immunity to the allergen and will be able to fight against it.

Initially, this method of therapy will probably appear like it’s making absolutely no changes, however, it works incredibly slowly. Immunotherapy can often take up to a full year to start having a positive impact. Even though it happens very slowly, it’ll be worth it in the end as your pup should see a huge improvement in their skin’s condition.


If your dog is experiencing dermatitis due to what they’re eating, it’s crucial for you to figure out the specific allergen and switch up their food in accordance.

Feeding your dog a nourishing, natural diet that contains bounds of natural ingredients with absolutely no nasties means your pooch’s skin should significantly improve and get back into great condition.

This is also where a personalised recipe can help. Pure caters for several allergies, just specify your pup’s allergy and some tailored, tasty dog food recipes will be created for your pooch. This means that they can enjoy healthy, nutritious food and you won’t have to worry about them eating something that’ll cause a reaction.

Even if your dog’s dermatitis is triggered by something airborne, functional ingredients in your dog’s food can help massively. Omega 3 fatty acids are an important ingredient in Pure, providing several benefits, such as reducing sore and inflamed skin. This is incredibly helpful for dogs suffering from dermatitis, calming the irritation and reducing your dog’s desire to itch.

Can I prevent my dog from getting dermatitis?

Sadly, there is no way to prevent your pup from developing dermatitis, some dogs do just have allergies which trigger the condition. Although, there are a few ways to help your dog.

If you know what your dog is allergic to, it may seem pretty obvious, but avoiding this substance is the best thing you can do to prevent any irritation. Of course, many of these substances can’t be avoided, such as grass and pollen. If you suffer from hay fever, you may be able to relate to how your friend is feeling, sometimes the pollen is just unescapable!

Dogs that suffer from parasitic allergy dermatitis need to have their flea treatment constantly maintained to prevent any parasites occupying your pooch. This will ensure your dog doesn’t get bitten by parasites where they’ll subsequently suffer from an allergic reaction.

Frequent dusting and vacuuming can help reduce the chances of reactions if you suspect dust is the root of dermatitis.

Also, taking the extra time to give your dog’s coat a quick rinse after a walk in the park can work wonders to remove any pollen or grass that may be lurking in their fur.


Dogs that suffer with dermatitis will probably have to deal with this skin condition for the rest of their lives as you can’t really get rid of allergies completely. However, with the appropriate treatment, your pooch should be saying goodbye to the itchiness, inflammation and discomfort.

Overall, if you’re able to pinpoint exactly what your pup is allergic to, you’ll have a much better chance of giving them a life where they can live happily, comfortably and itch-free.

  1. Canine atopic dermatitis: Detailed guidelines for diagnosis and allergen identification BMC veterinary research, 196, (11), August 2015,