Allergy Testing – Intradermal Skin Testing or Serum Allergy Testing

Some pets with allergic skin disease will respond nicely to the occasional cortisone injection and a round of antibiotics, but for some the itching seems relentless. When the pet’s allergies continue to get worse or become a year round battle, allergy testing and de-sensitization can be a useful diagnostic tool and treatment. However, it is not perfect. False positives, false negatives and cross reaction can occur. The tests available for our pets is the intradermal skin tests and the newer serum allergy testing.

intraderrmal allergy testingIntradermal allergy testing has been the gold standard for allergy testing in both humans and pets for years. To perform the test, the pet must not have had any cortisone or antihistamines for at least 2 weeks prior to testing. The pet is then sedated and an area on their skin is shaved. Small marks are made on the dog and then a small amount of the suspected allergen is injected into the skin. After 20 minutes, the wheal or reaction is then measured and compared to the control histamine injection.  The allergens that created a reaction are then identified.

Intradermal allergy testing is expensive, time consuming and usually done by an veterinary dermatologist. The allergens to perform the tests are expensive for the veterinarian to purchase  and have a short shelf life, so unless the veterinarian is performing the tests on a daily basis, they will probably refer the pet to a specialist to perform the diagnostic testing.

The newer serum allergy testing has made a dynamic positive impact on allergy testing for the general practice veterinarians. This technology tests the dog’s serum for specific IGG or immunoglobulins¬† (antibodies) that have been identified to react to specific allergens. To test your dog, blood is drawn and sent to an allergy laboratory, such as, and panels are done. Regional panels have identified the most common grasses, trees, molds, etc. that cause allergies in the area that you live. The food panel can identify basic food groups that the dog may be allergic to. Once the blood is analyzed, a report is returned to your veterinarian. The advantage to this allergy testing is that it can be done by any veterinarian, does not require shaving, sedation or a withdrawal of the cortisone prior to the testing. The tests will identify the specific allergen the pet had a reaction and this can be used to order the immunotherapy to help with desensitization of your pet to the allergens. The immunotherapy can be in the form of injections or in a new form, oral allergy drops ( The oral allergy drops have increased client compliance in giving their pet the immunotherapy and in some pets, an improvement in their allergies seems to occur much faster than with injections.

Studies have been done and show that after a dog is 2 years of age or older, there is not much statistical difference between the results of the intradermal testing or the serum testing. This allows more pets to undergo allergy testing at their family veterinarian office and with the new oral allergy drops, pet owners no longer have to give injections to their dogs and are more likely to undergo the immunotherapy. We now offer the serum allergy testing and the oral allergy drops to our patients with allergies.

Be Sociable, Share!


  1. […] Identifying the allergen with allergy testing […]

Speak Your Mind