Diagnosing allergic rhinitis usually starts with a detailed medical history, and may include a skin test to identify particular allergens. Dr. Patel, can you tell us more about the diagnosis of allergic rhinitis?
Absolutely, Dr. Green. A provider may do a physical examination and ask about the frequency and severity of symptoms. They may also ask whether symptoms vary by time of day or season. Other clues that can help a provider pinpoint the cause of symptoms include information about work and home environments, eating habits, and family medical history.
If this information is inconclusive, a provider may recommend a blood test that detects and measures allergen-related antibodies in the blood. This test can look for several allergens at once.
A provider may also recommend a skin test, in which small amounts of suspected allergens are introduced into the skin to look for allergic reactions. Skin testing is the easiest and, in many cases, the most effective way of identifying allergens.
There are two types of skin tests that may be used: the prick or scratch test, and the intradermal test.
In the prick or scratch test, also known as a percutaneous test, a tiny drop of a possible allergen is pricked or scratched into the skin. This is the most common type of skin test, and results are usually available in 10 to 20 minutes.
The intradermal test is typically more sensitive than the prick or scratch test. In this test, a small amount of a possible allergen is injected under the skin using a thin needle. The site is checked for a reaction after about 20 minutes.
A skin test can help identify precisely which allergen or allergens are causing symptoms. This information is useful in the management and treatment of allergic rhinitis.