Ask the Vet: Itchy Dogs and Allergy Management

Yellow Labrador puppy sits in grass and scratches at his green collar.

Many dogs are prone to allergies, and symptoms are not necessarily the same as a person’s. Humans sneeze, get runny eyes, or a scratchy throat. Dogs may manifest allergies in the skin, such as frequent ear infections, skin and lip fold infections, or anal gland impactions. They can be very itchy, shake their heads, scratch their ears, lick their feet excessively, or scoot along their rear ends. If the underlying cause can be addressed, then itchiness can be reduced.

Allergies are categorized into three major groups, and most dogs with allergies are affected to a varying degree by all three: fleas, food, and environmental/seasonal allergens.

Fleas are the most common cause of allergies and the easiest to address. For affected dogs, one fleabite can set off the allergic reaction. Many older topical flea preventatives don’t work as quickly as they used to and they lose efficacy when dogs swim or get bathed frequently. All itchy dogs, regardless of the allergy, should be on an oral flea preventative like Comfortis, Nexguard, Bravecto, or Trifexis. Flea prevention should be given year-round at the dosage and dates recommended by your veterinarian. Every other household animal, including indoor cats, must be on regular flea prevention as well.

Food allergies can also cause symptoms, and treating them is a process of trial and error. Your vet will recommend a diet change, or a “food trial,” if he suspects a food allergy, and no other types of food or treats can be fed during this time. The most common culprits of food allergies are the protein source in dog food, not gluten or grain as many claim. Some dogs will show improvement within 4 weeks of a food trial, but 12 weeks of strict adherence to the new food are required to determine a true response. If the itching doesn’t improve in 12 weeks, it doesn’t necessarily mean the dog doesn’t have a food allergy; it could be that the right diet hasn’t been found.

Environmental allergies can have similar symptoms to food allergies, and can be seasonal or year round. Dogs with seasonal environmental allergies are itchiest the same time every year, usually spring or fall. Environmental allergies can be managed many ways, depending on the frequency and severity of symptoms. For mild environmental allergies, the following approach is recommended:

  • Bathing as often as once a week in a soap-free oatmeal shampoo helps remove allergens off the skin and decreases itching. For a dog that licks his feet excessively, baby wipes can be used daily or every other day to remove allergens from the feet.
  • Antihistamines such as Benadryl can be given twice daily for at least two weeks before determining if your dog is responding. A dog needs 1 mg of Benadryl per pound of body weight, so a 50 lb. dog will get 50 mg of Benadryl, for example.
  • Fish oil acts as a natural anti-inflammatory that can decrease itching. Dogs weighing 60 – 100 lbs. can have about 2,000 mg of fish oil on their food per day. These can be purchased at your local drug store or online.
  • If the itching is severe enough that bathing, antihistamines, and fish oil do not help, your veterinarian may recommend stronger medications.

Allergy management can be frustrating and expensive, depending on the frequency and severity of symptoms. Try these tips at home to help relieve your itchy dog. Now you have a better understanding of the step-wise approach your vet may take when managing your dog’s allergies.

Posted on August 9, 2017 | Category: Ask the Vet, Blog