Dog Allergies: Food Vs Seasonal What You Need To Know

Learn to identify, differentiate and treat the most common allergies affecting your canine companion

By Shinta

Sep 1, 2025

Learn to identify, differentiate and treat the most common allergies affecting your canine companion

Image: HearthJunction Design Team

Understanding Allergies in Dogs: Food vs Seasonal

Just like humans, dogs can suffer from a variety of allergies that affect their quality of life. If you’ve noticed your dog scratching excessively, developing skin issues, or showing other signs of discomfort, allergies might be the culprit. The two most common types of allergies in dogs are food allergies and seasonal/environmental allergies. Understanding the difference between these conditions is crucial for proper diagnosis and effective treatment of your furry friend.

While these allergies can present with similar symptoms, their causes, diagnosis methods, and treatment approaches differ significantly. This comprehensive guide will help you identify the signs of allergies in your dog, understand the underlying causes, and learn about the various treatment options available.

Dog Allergy Symptoms: What to Look For

Before diving into the specific types of allergies, it’s important to recognize the common symptoms that might indicate your dog is suffering from an allergic reaction. Many of these symptoms overlap between food and seasonal allergies, which can make initial identification challenging.

Common Allergy Symptoms in Dogs

Itchy skin (pruritus) â often the most noticeable symptom
Excessive scratching and licking of self
Excessively rubbing the face on the floor or furniture
Red, inflamed skin
Skin infections
Hair loss or bald patches
Ear infections or inflammation (red, smelly ears)
Head shaking
Hot spots (acute moist dermatitis)
Skin that flakes or appears dry

In addition to these skin-related symptoms, dogs with food allergies may also experience gastrointestinal issues such as vomiting, diarrhea, or decreased appetite. These digestive symptoms are less common with seasonal allergies.

It’s important to note that persistent scratching and licking can lead to secondary problems like bacterial or yeast infections, which may require additional treatment. If you notice any of these symptoms, consulting with your veterinarian should be your first course of action.

Types of Allergies in Dogs

Dogs can develop several types of allergies. Understanding the characteristics of each type can help you and your veterinarian determine the most likely cause of your dog’s symptoms.

Seasonal/Environmental Allergies

Also known as atopy, seasonal or environmental allergies are caused by substances that exist in your dog’s surroundings. These allergens can be inhaled, as with pollen, or absorbed through the skin when your dog comes into contact with them.

Common triggers (allergens) for environmental allergic reactions include:

Pollens from trees, grasses, and weeds
Mold spores
Dust mites
Dander
Plant or animal fibers
Household chemicals or cleaners

Some environmental allergiesâsuch as allergies to certain pollensâmay occur seasonally, typically peaking during spring or fall. Other environmental allergies, like allergies to dust mites, may occur year-round (perennial allergies).

Your dog’s climate and environment can have a major impact on whether they develop seasonal allergies. In warmer climates where plants bloom year-round, dogs may be continuously exposed to allergens. In contrast, in areas with distinct seasons, allergies might be more pronounced during specific times of the year.

It’s worth noting that allergies can evolve over time. A dog that initially has seasonal allergies may eventually develop year-round symptoms, especially as they age. This occurs because repeated exposure to allergens can intensify allergic responses over time.

Flea Allergies

An allergy to fleas is the most common skin disease in dogs. What many pet owners don’t realize is that the bite of just one or two fleas per week is enough to make affected dogs extremely itchy. It’s not the flea itself but proteins in flea saliva that trigger the allergic reaction.

With flea allergies, you may or may not see live fleas on your dog. However, you might notice black dots that look like coffee grounds at the base of your dog’s fur. These black dots are flea dirt (flea excrement) and contain digested blood.

Food Allergies

Dogs can develop an allergy to a particular food at any point during their life, even if they’ve been eating the same diet for years without problems. Most commonly, the allergy is to a specific ingredient in the food rather than the entire diet.

The most common food allergies in dogs are to protein sources in their diet, such as:

Beef
Chicken
Dairy
Egg
Lamb
Fish

While allergies to grains or other ingredients can occur, they aren’t as common as protein allergies. It’s important to distinguish between true food allergies (which involve the immune system) and food intolerances (which typically don’t involve the immune system but may cause similar symptoms).

Food Allergies vs. Seasonal Allergies: Key Differences

Although food allergies and seasonal allergies can cause similar symptoms, there are several key differences that can help distinguish between them:

Characteristic	Food Allergies	Seasonal/Environmental Allergies
Timing	Present year-round as long as the allergenic food is consumed	May be seasonal or year-round depending on allergen exposure
Response to treatment	Respond to dietary changes; elimination of allergenic food	Respond to antihistamines, steroids, and environmental management
Gastrointestinal symptoms	More common (vomiting, diarrhea, decreased appetite)	Less common
Age of onset	Can develop at any age	Often begins when dog is young (1-3 years)
Diagnostic approach	Food elimination trials	Intradermal skin testing, blood tests

It’s important to note that there is also some overlap between these conditions. According to veterinary nutritionists, approximately 30 percent of pets with food allergies also have seasonal allergies or allergies to fleas. This can make diagnosis more challenging and may require a comprehensive approach to management.

Diagnosing Allergies in Dogs

Proper diagnosis is essential for effective allergy management. Your veterinarian will likely use different approaches depending on the suspected type of allergy.

Diagnosing Seasonal/Environmental Allergies

For seasonal or environmental allergies, diagnosis may involve:

Detailed medical history, including when symptoms occur
Physical examination
Ruling out other conditions (like parasites or infections)
Intradermal skin testing (similar to allergy testing in humans)
Blood tests to detect allergen-specific antibodies

Your veterinarian may also recommend a trial of antihistamines or other allergy medications to see if your dog’s symptoms improve.

Diagnosing Food Allergies

Food allergies are typically diagnosed through food elimination trials. This process involves:

Feeding your dog a diet with novel protein and carbohydrate sources (ones your dog has never eaten before) or a hydrolyzed protein diet
Strictly maintaining this diet for 8-12 weeks
Avoiding all other foods, treats, and flavored medications during this period
Monitoring for improvement in symptoms
Conducting food challenges by reintroducing original foods one at a time to identify specific allergens

Blood and skin tests for food allergies are generally considered less reliable than elimination trials. Your veterinarian will guide you through the appropriate diagnostic process based on your dog’s specific situation.

Treatment Options for Dog Allergies

Treatment approaches vary depending on the type of allergy your dog has. In many cases, a multi-faceted approach works best to manage symptoms and improve your dog’s quality of life.

Treating Seasonal/Environmental Allergies

Management options for seasonal allergies include:

Antihistamines to reduce itching and inflammation
Corticosteroids for short-term relief of severe symptoms
Immunotherapy (allergy shots) to desensitize the immune system
Specialized medications like Apoquel or Cytopoint that target specific pathways in the allergic response
Medicated shampoos to soothe irritated skin
Omega-3 fatty acid supplements to support skin health
Environmental management (air purifiers, regular cleaning, limiting outdoor time during high pollen seasons)

Your veterinarian may recommend a combination of these approaches based on the severity of your dog’s symptoms and their specific allergens.

Treating Food Allergies

The primary treatment for food allergies is avoidance of the allergenic ingredients. This typically involves:

Feeding a hypoallergenic or limited-ingredient diet
Strictly avoiding the identified allergens in all food, treats, and even medications
Monitoring for any changes in symptoms
Treating secondary infections or complications as needed

Once the allergenic food has been identified and eliminated, most dogs show significant improvement within a few weeks, though complete resolution of symptoms may take longer.

Living with a Dog with Allergies: Management Tips

Living with a dog with allergies requires ongoing management and attention. Here are some tips to help make life more comfortable for your allergic pet:

Follow your veterinarian’s treatment plan consistently
Keep a diary of symptoms to identify patterns or triggers
Bathe your dog regularly with gentle, hypoallergenic shampoos to remove allergens from the coat
Wipe your dog’s paws and coat after walks to remove environmental allergens
Use high-efficiency air filters in your home
Wash your dog’s bedding frequently in hot water
Consider protective clothing (like dog t-shirts) to limit contact with environmental allergens
Be vigilant about flea prevention, even if fleas aren’t the primary allergy
Read all ingredient labels carefully if your dog has food allergies

Remember that allergies are typically a lifelong condition that requires ongoing management. With proper care and attention, however, most allergic dogs can lead happy, comfortable lives.

When to See a Veterinarian

While mild allergy symptoms might be manageable at home, you should consult with your veterinarian if:

Your dog’s symptoms are severe or getting worse
Your dog develops secondary infections
Your dog is uncomfortable or in pain
Home management isn’t providing relief
You notice new or different symptoms

Early intervention can prevent more serious complications and help your dog find relief sooner. Don’t hesitate to seek professional advice if you’re concerned about your dog’s allergies.

Frequently Asked Questions (FAQs)

Q: Can dogs outgrow their allergies?

A: Unlike some children who outgrow allergies, dogs rarely outgrow their allergies. In fact, allergies in dogs often worsen with age and continued exposure to allergens. However, with proper management, symptoms can be controlled effectively.

Q: Are certain dog breeds more prone to allergies?

A: Yes, some breeds seem to have genetic predispositions to allergies. Breeds like Golden Retrievers, Labrador Retrievers, West Highland White Terriers, Boxers, and Bulldogs are more commonly affected by allergies than others.

Q: Can changing my dog’s diet help with environmental allergies?

A: While diet primarily addresses food allergies, some dogs with environmental allergies may benefit from high-quality diets rich in omega-3 fatty acids, which support skin health and may reduce inflammation. However, diet alone won’t resolve environmental allergy symptoms.

Q: How long does it take to see improvement after starting allergy treatment?

A: Timeline varies depending on the treatment approach. Medications like antihistamines or corticosteroids may provide relief within days, while food elimination diets typically require 8-12 weeks to show full results. Immunotherapy can take several months to become effective.

Q: Can my dog have both food and environmental allergies simultaneously?

A: Yes, approximately 30% of dogs with food allergies also have environmental allergies or flea allergies. This is why a comprehensive diagnostic approach is important for dogs with persistent allergy symptoms.

References

Author

Shinta

Shinta is a biotechnologist turned writer. She holds a master's degree in Biotechnology from Karunya Institute of Technology and Sciences and a PG Diploma in cellular and molecular diagnostics from Manipal University. Shinta realised her love for content while working as an editor for a scientific journal.

Read full bio of Shinta