Quick Answer:Environmental allergies (pollen, grass, dust mites) tend to be seasonal, affect the paws, belly, and ears, and often start between ages 1 and 3. Food allergies cause year round symptoms, often with digestive signs alongside itching, and can start at any age. The only reliable way to confirm a food allergy is an elimination diet supervised by your vet. |
This is one of the most confusing things about owning an itchy dog. You know something is making them uncomfortable. But is it the grass? The chicken in their food? The dust mites in the carpet? Something else entirely?
I spent years trying to work this out with Lola, my late Frenchie. She was itchy constantly and I kept changing her food, convinced it was something she was eating. It took a long time (and a lot of wasted money on different kibbles and raw diets) before I understood what I was actually dealing with.
So let me save you some of that time.
Environmental Allergies: The Seasonal Scratchers
Environmental allergies (vets call them atopic dermatitis) are by far the most common type of allergy in dogs. They are triggered by things your dog breathes in or touches: pollen, grass, mould spores, dust mites, and even certain cleaning products.
The typical pattern:
✔️ Symptoms that get worse at certain times of year (spring and summer for pollen, autumn for mould, year round for dust mites)
✔️ Itching concentrated on the paws, belly, armpits, groin, and ears
✔️ Red, irritated skin in those areas
✔️ Paw licking and chewing (sometimes to the point of rust brown staining)
✔️ Recurrent ear problems
✔️ Usually starts between 1 and 3 years of age
Summer is the worst for this. Her name is ironic, because summer is genuinely her worst season. She is Hazel's dog, and when the pollen count climbs, Summer's whole body flares up. She lost an eye in 2025, and managing her allergies is a year round commitment. The heat seems to make everything worse for dogs with sensitivities.
The key thing about environmental allergies is that you cannot really avoid the trigger. Your dog needs to go outside. Pollen is everywhere. Dust mites are in every home. So the goal is managing the symptoms and supporting the skin, not eliminating the cause.
Food Allergies: The Year Round Itch
True food allergies are less common than most people think. Studies suggest they account for around 10 to 15% of all allergic skin disease in dogs. But they are often the first thing owners suspect, which leads to a lot of unnecessary dietary changes.
The typical pattern:
✔️ Year round symptoms that do not change with the seasons
✔️ Itching that often affects the face, ears, paws, and rear end
✔️ Digestive signs alongside the itching: soft stools, wind, gurgling, vomiting, or diarrhoea
✔️ Can start at any age (including puppies under 6 months, which is unusual for environmental allergies)
✔️ Does not respond to antihistamines (which may help environmental allergies)
The most common food allergens in dogs are proteins: beef, chicken, dairy, and wheat are the usual suspects. And here is the important bit: the only reliable way to identify a food allergy is a proper elimination diet, ideally supervised by your vet. Blood tests for food allergies in dogs are widely considered unreliable. I know that is frustrating, but it is the truth.
Gus, my Frenchie, has the most sensitive tummy of all our dogs. Any change in his food sets him off. But his sensitivity is more of a digestive intolerance than a true allergy. The difference matters, because the approach is different.
How to Tell Which One Your Dog Has
Here is a simple comparison that might help you narrow it down.
Seasonal pattern?
Environmental: Yes, often worse in spring/summer or specific seasons.
Food: No, consistent year round.
Where does the itching happen?
Environmental: Paws, belly, armpits, groin, ears.
Food: Face, ears, paws, rear end. Often more widespread.
Digestive symptoms?
Environmental: Rarely.
Food: Common. Soft stools, wind, vomiting, diarrhoea alongside skin signs.
Age of onset?
Environmental: Usually between 1 and 3 years.
Food: Any age, including very young puppies.
Response to antihistamines?
Environmental: Sometimes helpful.
Food: Usually no improvement.
The test?
Environmental: Intradermal skin testing or blood allergy panel (via your vet).
Food: Elimination diet (8 to 12 weeks of a novel protein or hydrolysed diet).
What About Dogs That Have Both?
This is the really frustrating bit. Some dogs have both environmental and food allergies at the same time. Their allergy "threshold" is already high from the environmental triggers, and a food sensitivity pushes them over the edge.
If your dog is itchy year round but gets dramatically worse in certain seasons, there is a good chance both are at play. Your vet can help you work through this systematically.
Summer, Hazel's dog, is very reactive. Her skin flares up at the slightest thing. When you are dealing with a dog like Summer, it becomes about managing the total allergic load, reducing as many triggers as you can so the body is not constantly overwhelmed.
What You Can Do at Home
While your vet works on diagnosis, there are practical things you can do to help support your dog's comfort.
For environmental allergies:
✔️ Wipe paws and belly after walks (removes pollen and grass contact)
✔️ Wash bedding weekly on a hot wash
✔️ Keep grass short in your garden
✔️ Bathe with a gentle, natural shampoo to remove surface allergens
✔️ Consider a supplement that helps support skin comfort and natural environmental harmony
Our Environmental Harmony collection is formulated by qualified herbalists and nutritionists to help support dogs dealing with seasonal and environmental sensitivities. It helps support natural comfort and a balanced response to environmental triggers.
For food allergies:
✔️ Work with your vet on a proper elimination diet
✔️ Keep a food diary (every ingredient, every treat, every chew)
✔️ Be strict during the trial (one stolen treat can invalidate weeks of work)
✔️ Support digestion during the transition
Our Digestive Harmony collection can help support healthy digestion during dietary changes. Gut health and skin health are closely connected, and supporting one often helps the other.
When to See Your Vet
Please see your vet if:
✔️ Your dog is intensely itchy and nothing seems to help
✔️ The skin is broken, weeping, or infected
✔️ You suspect a food allergy (the elimination diet needs proper supervision)
✔️ Symptoms are getting worse despite your best efforts
✔️ Your dog is losing fur, losing weight, or seems unwell
If the skin is broken or sore, please see your vet first. Infections need proper treatment, and I would always rather say that than have you guessing.
Allergy testing (either skin prick testing or blood panels for environmental allergies) can give you real answers and help you target your approach. It is worth the investment, especially if you have been going round in circles trying to work it out yourself.
The Bottom Line
Environmental allergies are common, seasonal (usually), and managed rather than cured. Food allergies are less common, year round, and diagnosed through elimination diets. Some unlucky dogs have both.
The most important thing is getting the right diagnosis so you are treating the right problem. A dog on an expensive novel protein diet for a suspected food allergy that actually has environmental atopy is not going to improve, and that is months of frustration for everyone.
If you want to explore our allergy support range, everything is formulated by qualified herbalists and nutritionists and trusted by over 400,000 dogs. For itchy skin support, browse our Dermal Comfort collection. Because understanding the problem is always the first step to helping them feel better. 🐾
FAQs
#1: How do I know if my dog has a food allergy or environmental allergy?
The biggest clues are timing and digestive symptoms. Environmental allergies tend to be seasonal and affect paws, belly, and ears. Food allergies cause year round symptoms, often with digestive signs like soft stools or vomiting alongside the itching. Your vet can help confirm the diagnosis with testing or an elimination diet.
#2: What is the most common allergy in dogs?
Environmental allergies (atopic dermatitis) are the most common type. They are triggered by pollen, grass, dust mites, and mould spores. True food allergies account for only around 10 to 15% of allergic skin disease in dogs, though they are often suspected first.
#3: Are dog food allergy blood tests accurate?
Blood tests for food allergies in dogs are widely considered unreliable by veterinary dermatologists. The only dependable way to diagnose a food allergy is a supervised elimination diet lasting 8 to 12 weeks. Blood tests for environmental allergies are more useful.
#4: Can dogs develop allergies later in life?
Yes. Environmental allergies most commonly appear between 1 and 3 years of age, but can develop at any time. Food allergies can also start at any age, including in senior dogs. If your older dog suddenly becomes itchy, it is worth investigating with your vet.
#5: What can I give my dog for allergies naturally?
Natural supplements formulated with botanical ingredients can help support skin comfort and a healthy response to environmental triggers. Washing paws after walks, regular gentle bathing, and supporting gut health can all help alongside any approach your vet recommends.
