Diagnosis of Dust Mite Allergy
To diagnose a dust mite allergy, your doctor may give you a physical exam and discuss your symptoms. If your doctor thinks you have a dust mite allergy, they may suggest a skin or blood test. If you have symptoms year round, you could have a dust mite allergy.

Skin Prick Test (SPT)
In prick/scratch testing, a small drop of the possible allergen is placed on your skin. Then the nurse or doctor will lightly prick or scratch the spot with a needle through the drop. If you are allergic to the substance, you will develop redness, swelling and itching at the test site within 20 minutes. You may also see a wheal. A wheal is a raised, round area that looks like a hive. Usually, the larger the wheal, the more likely you are to be allergic to the allergen.

A positive SPT to a particular allergen does not necessarily mean you have an allergy. Health care providers must compare the skin test results with the time and place of your symptoms to see if they match.

Specific IgE Blood Test
Blood tests are helpful when people have a skin condition or are taking medicines that interfere with skin testing. They may also be used in children who may not tolerate skin testing. Your doctor will take a blood sample and send it to a laboratory. The lab adds the allergen to your blood sample. Then they measure the amount of antibodies your blood produces to attack the allergens. This test is called Specific IgE (sIgE) Blood Testing. (This was previously and commonly referred to as RAST or ImmunoCAP testing.) As with skin testing, a positive blood test to an allergen does not necessarily mean that an allergen caused your symptoms.