Dog & Cat Allergies: Causes, Symptoms & Treatment

Why Is My Dog Itchy?

Common Causes of Allergies in Dogs

The two most common causes of chronic itching in dogs are external parasites and allergies. Itching can appear as scratching, but dogs may also lick, chew, or rub their skin.

Common causes include:

• Flea allergies - see below
• Environmental allergies - see below
• Secondary skin or ear infections: Allergies can contribute to recurring bacterial or yeast infections, which can increase inflammation and make your dog's itching worse.
  • It is important to work with your veterinarian to fully treat any infections so we can properly determine how much of the itching is due to the allergies versus the infection.
• Food allergies - see below
• Other skin conditions: Parasites and other dermatologic conditions can cause symptoms that look similar to allergies, which is why identifying the underlying cause is important. Some examples are ringworm fungal infections, skin mites/mange and autoimmune diseases.

Flea Allergies in Dogs

• Some dogs are extremely sensitive to flea saliva, and even a few flea bites can cause significant itching. You may not always see fleas on your pet, particularly if your dog is scratching frequently. 
  • *Note: Not all animals will itch when they have fleas. You cannot assume your pet does not have flea exposure just because the other pets in the house are not itching. Often the ones not itching carry the most fleas because they aren't obsessively grooming them off. Indoor cats that don't show flea allergies are notoriously major sources of fleas inside the house as they continue to feed the indoor population of fleas while owners are only treating the pet that is itching.

Learn more about Parasites and prevention→ 

Environmental Allergies in Dogs

• Dogs can react to allergens such as pollens, house dust mites, and other substances in their environment. Dogs with allergies most commonly develop itchy skin rather than respiratory symptoms.
  • At a minimum, pets with environmental allergies should be wiped down with a damp cloth daily, bathed with appropriate shampoo or at least rinsed down well up to 3 times per week or as instructed. Avoid fresh cut grass, overgrown or thick brush areas and some may do best keeping walks to paved areas during their allergy season.

Food Allergies in Dogs

Food allergies can also cause itching and skin problems in dogs. Dogs may develop an allergic reaction to a protein or other ingredient in their food. Signs can include year-round itching, particularly involving the paws, ears, face, or other areas of the skin. Some dogs may also experience gastrointestinal signs such as vomiting or diarrhea.

Food allergies can be difficult to confirm because the symptoms can look very similar to environmental allergies. When a food allergy is suspected, your veterinarian may recommend a strict elimination diet trial using a specially selected diet. During the trial, it is important that your dog receives only the recommended food and does not receive other treats, table food, flavored medications, or supplements unless approved by your veterinary team. This helps determine whether food is contributing to your dog's symptoms.

If food allergies are suspected, please work with your veterinarian to implement an effective food trial to properly diagnose and develop a future plan for your pet.

Food Allergies in Dogs and Cats - Veterinary Partner - VIN
Implementing an Elimination-Challenge Diet Trial Dog | VCA Animal Hospitals
Food trial instructions

How Are Pet Allergies Treated?

Allergies Are Usually Managed, Not Cured

Allergies in dogs are generally considered a long-term condition. The goal is to control itching and inflammation, address any secondary infections, identify contributing factors, and improve your dog's comfort and quality of life.
For some, this will never be 100% resolution of itching but the goal is to minimize it to a level that doesn't take over their life and create constant infections as well as reduce the frequency and severity of major flare ups.

Your veterinarian can help determine whether your dog's itching is related to fleas, environmental allergies, food allergies, infection, or another condition and develop an appropriate treatment plan.

When Should You Contact Your Veterinarian?

Please let us know if your dog is experiencing:

• Persistent or worsening itching
• Excessive paw licking or chewing
• Hair loss or red, irritated skin
• Recurrent ear infections
• Skin odor, scabs, or sores
• Frequent flare-ups despite flea prevention

If your dog or cat is experiencing persistent itching, paw licking, ear infections, or skin irritation, our Tampa Bay veterinary team can help determine whether allergies, parasites, infection, or another condition may be contributing.

Additional Resources

Skin health with Douxo products:
02-itchy skin relief-dog
DOUXO® - #1 Topical Brand Recommended by Veterinarians

For additional information, here are links to some useful resources:

Itching and Allergy in Dogs - Veterinary Partner - VIN
Atopic Dermatitis in Dogs - Veterinary Partner - VIN
Itch Relief for Dogs and Cats - Veterinary Partner - VIN

If your dog or cat is experiencing persistent itching, recurrent ear infections, paw licking, hair loss, or skin irritation, Paws Bay Animal Hospital can help determine the underlying cause. We proudly serve pet families in Tampa, Oldsmar, Westchase, Town 'n' Country, Citrus Park, Upper Tampa Bay, and surrounding communities.