Allergies in Dogs
Does your dog have allergies? He may, if he has any of the following allergy symptoms:
- Scratches his ears
- Licks or chews his feet or body
- Has a reddish discoloration of the hair on the paws or between the toes
- Rubs his face against the furniture or floor
- Has a rash, bumps, pimples or open sores on the skin
- Has red or watery eyes
- Has ear infections
- Has sneezing or a runny nose
- Vomits or has diarrhea
- Coughs or wheezes
Dogs tend to have different allergy symptoms than people do. While grass pollen may cause a person to sneeze and have watery eyes, a dog may develop itchy feet that causes him to lick and bite. Although dogs can develop watery eyes and sneezing, the most common allergy symptom is scratching. Constant scratching may lead to open sores, raised welts and loss of hair.
All dog breeds can be affected by allergies. Allergies usually affect dogs over two years old, although they have been reported in dogs as young as five months old. This means that dogs who are affected by allergies often suffer their entire lives and symptoms often become worse with age. As a dog owner, it is important to educate yourself about allergy symptoms and treatment options to help keep your best friend comfortable.
Types of Dog Allergies
There are four types of dog allergies. These include:
- Airborne allergies (atopy)
- Flea allergies
- Food allergies
- Contact allergies
Airborne Allergy (Atopy)
Allergies to particles (allergens) your dog inhales is called atopy and is very common. Common allergens include tree pollens (cedar, ash, oak, etc), grass pollens, weed pollens (ragweed, goldenrods, etc), molds, mildew and house dust mites. Many of these allergies occur seasonally, such as ragweed and grass pollens. Others, such as molds, mildew and house dust mites are year-round problems. When humans inhale these allergens they usually develop respiratory signs ("hayfever"). When dogs inhale these allergens they develop itching of the face, feet and armpits.
One of the most important treatments is to minimize your dog's exposure to things he is allergic to. For example, if a dog is allergic to pollen, he should be kept inside when pollen counts are high or the grass is being mowed. Air filters can also help remove many airborne allergens to keep the home environment clean.
Some veterinarians will recommend allergy shots if specific allergens have been identified (see allergy testing below). With allergy shots, very small amounts of the offending allergen are injected weekly to help your dog become less sensitive to it. Up to 75% of dogs that receive allergy shots will have improvement in their signs—but it can take several months (up to one year) to see the full effect.
Flea allergy is a very common allergy in dogs. Most dogs will have minor irritation and itching from a flea bite. A dog with flea allergy, however, will have a severe reaction to a single flea—they will often bite and break the skin and even remove large patches of their own hair. The most common area of the body affected by flea allergy is the base of the tail or the hind legs.
Treatment of flea allergy includes strict flea control. Fleas can be very difficult to kill but with modern flea medicine and home treatment options, your veterinarian can help you rid your home and dog of these pests.
Food allergies are more common than originally thought, and it is now known that food allergy and atopy often occur together. Food allergy can strike at any age and allergies can develop to any protein or carbohydrate in the food. Allergies to beef, pork, chicken, turkey, eggs, soy, corn and wheat seem to be the most common. Common symptoms of dog food allergy include itching of the face, feet, sides of the body, legs and anal area. These dogs will often have ear yeast infections and skin infections that respond to antibiotics, but recur as soon as the antibiotic is finished. Some dogs with food allergy will also have increased bowel movements and soft stool. Food allergies should not be confused with food intolerances which generally cause more severe vomiting and diarrhea.
Treatment of food allergy involves feeding your dog a diet that does not contain the allergen. To achieve this, your veterinarian will perform a "diet trial". A commercial hypoallergenic diet or homemade dog food is prescribed and fed for 8 to 12 weeks. During this time, your dog must ONLY eat the prescribed food—no table food, scraps, treats, vitamins or chewable medications (even heartworm pills) can be given during a diet trial. If a positive response is seen after this trial, your veterinarian will advise you on how to proceed.
This is the least common type of allergy and is caused by something your dog comes in contact with, such as carpet, bedding, plastic, cleaners, detergents, lawn chemicals, grasses, or other things. The area of the body affected is the contact surfaces, such as the stomach, bottom of the feet, muzzle or elbows. Treatment involves identifying and removing the allergen.
Diagnosis of Allergies
If you suspect your dog has allergies, you should see your veterinarian. Veterinarians will usually make a preliminary diagnosis and treatment plan based on the following information:
- Season(s) of the year when your dog has the most symptoms
- What body locations are the most itchy
- Response of the itch to medications (e.g. shampoos, antihistamines, steroids, etc)
If the initial treatment does not give your dog relief, your veterinarian may recommend more specific "allergy testing". Allergy testing is done by either taking a blood test or performing intradermal skin testing. The blood tests are reasonably reliable for detecting airborne allergies but not as good for food or contact allergies. Skin testing is considered more accurate and involves shaving a patch of hair on your dog's side and then injecting small amounts of allergens under the skin. A positive test is diagnosed if there is a reddening or welting of the skin after injection. Those allergens can then be mixed together by a laboratory and injections given weekly at home over several months to help diminish the dog's reaction to the allergens.
Treatment of Allergies
In addition to specific treatments listed above for each allergy type, your veterinarian may recommend the following skin treatments to give your allergic dog relief during his most itchy times:
- Shampoo -- frequent bathing with a natural shampoo removes pollens, debris and other allergens from the coat that could be absorbed through the skin. Your veterinarian may prescribe a medicated shampoo or conditioner that contains anti-inflammatory ingredients if your dog needs additional relief.
- Anti-inflammatory allergy medication -- steroids, antihistamines or cyclosporine may be prescribed as they dramatically block the allergic reaction in most cases. These medications create almost immediate relief from skin irritation and severe itching associated with most types of allergy.
- Antibiotics -- often the itch of allergy is made worse by bacterial or yeast skin infections. Your veterinarian may recommend the use of oral antibiotics or anti-yeast medications to treat these infections.
Additional things you can do at home to minimize your dog's itchiness or allergy symptoms:
- Try to minimize the exposure of your dog to the suspected allergens.
- Feed your dog a high quality natural dog food with proper pet supplements to ensure they have no dietary deficiencies.
- Give your dog a pet supplement with fatty acids to provide beneficial anti-inflammatory properties and improve the quality of their skin and coat.
- Use stainless steel or glass feeding dishes and clean them regularly.
- Brush your dog's hair coat regularly to distribute the natural oils and prevent mats that can further irritate itchy skin.
- Apply a natural ointment in areas where the skin is broken or in "hot spots".
- Use flea preventative regularly as allergic dogs tend to be even more sensitive than normal dogs to flea or insect bites. A natural herbal dip is a gentle alternative to harsh chemicals.
- Wash your dogs bedding with hypoallergenic detergent in very hot water.
It can be miserable to watch your dog suffer with allergy symptoms. Using natural pet products and working closely with your veterinarian will ensure your dog will be as comfortable as possible.
Donna Spector, DVM, DACVIM,is a renowned, board-certified Veterinary Internal Medicine Specialist who has practiced at the Animal Medical Center in New York City and other leading institutions. She is an active member of the American Veterinary Medical Association (AVMA) and the American Holistic Veterinary Medical Association. Dr. Donna has written and lectured extensively on topics including nutrition, diabetes, gastrointestinal disorders, kidney failure and respiratory disease. She is widely recognized for her role as consulting veterinarian to HALO, Purely for Pets, her TV appearances with Ellen DeGeneres and her widely-quoted pet health advice in print and on radio. Dr. Donna performs medical, nutrition and weight loss consultations for dogs and cats through her web-based veterinary consulting service, www.SpectorDVM.com.