Allergies in dogs

Allergies and intolerances explained clearly.

At a glance

What is it?: An overreaction of the immune system to substances that are actually harmless; intolerances often have similar effects.
Typical signs: Itching, licking, scratching, reddened skin, ear problems, sometimes diarrhoea.
Commonly affected: Any dog can be affected. Environmental allergies often first appear in young dogs.
Possible triggers: Flea saliva, environmental allergens such as pollen or mites, food components.

Reading time 3 minutes Skin & defences

When should you see a vet?

Persistent itching or skin problems should be checked by your vet. Go to the vet straight away if:

the face, lips or eyelids suddenly swell,
your dog becomes short of breath, vomits or collapses after an insect sting or contact with something,
open, weeping patches of skin develop or the itching is very severe.

With an allergy, your dog’s immune system overreacts to substances that are actually harmless, for example pollen, house dust mites, flea saliva or certain food components. Typical signs are itching, frequent licking and reddened skin. Persistent itching and skin problems should be checked by a vet, because parasites or infections can also be behind them.

Allergy or intolerance?

With an allergy, the immune system is involved. With an intolerance, the body does not tolerate something without an immune reaction behind it. Both can look similar. Your vet can find out what your dog has.

How do you recognize an allergy?

itching, scratching, licking and nibbling, often on the paws, belly, armpits or ears
reddened skin, rash or bald patches
ear infections that keep coming back
sometimes diarrhea, vomiting or more frequent bowel movements

Which types are there?

Flea allergy: Just a few flea bites can cause severe itching, often on the back in front of the tail.
Environmental allergy: Pollen, house dust or storage mites trigger itching. It often first appears in young dogs and can vary with the seasons.
Food allergy: The immune system reacts to a specific component in the food, often a protein.
Contact allergy: Less often, the skin reacts to substances it comes into direct contact with.

How does the vet find the trigger?

First, the vet rules out other causes such as fleas, mites or skin infections. If a food allergy is suspected, the vet may recommend an elimination diet over several weeks, which should only be carried out with veterinary guidance. For environmental allergies, blood or skin tests help narrow down the triggers. This takes patience, because several steps are often needed.

What happens next?

Many allergies stay with a dog for life. Together with you, the vet decides how itching and skin problems can be relieved and how contact with the trigger can be reduced.

What you can do in everyday life

Work with your vet to keep your dog protected against fleas all year round.
Keep a diary: when and where does the itching occur, and what has your dog eaten?
During pollen season, wipe paws and belly with a damp cloth after walks.
Don’t give anything on your own and stop your dog from scratching open sores.

Frequently asked questions about Allergies

Allergy or intolerance: what is the difference?

With an allergy the immune system reacts; with an intolerance, not necessarily. Both can look similar, and your vet can investigate.

How is the trigger found?

Through targeted tests and gradually ruling out possible causes, which can take some time. Tackle it together with your vet.

Why does my dog keep scratching?

Itching can be allergic but can also be caused by parasites or skin infections. That is why it should be investigated.

What can I do until the appointment?

Note when and where the symptoms occur, and keep your dog from scratching open sores as best you can. Don’t give anything on your own initiative.

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Veterinary expertise at the heart of our team

Dr. med. vet. Sibylle Ott has been part of our team at DOG FIT by PreThis^® from the very beginning. As an experienced vet, she supports our work professionally and contributes her knowledge of dog health. Her experience and her deep understanding of dogs’ needs are an important guide for us. She is a valuable treasure for our team and for the well-being of many dogs.

This content is for information only and does not replace advice from a vet. Our products are complementary feed for dogs. They do not replace a veterinary examination or treatment. If your dog has any health problems, please contact your vet.