Your doctor ask you will about your symptoms and health record. You may have questions about the foods you eat, your daily life, or if you notice problems at certain times. Your doctor will look inside your nose for signs of swelling and irritation. Your answers and the results of the exam may point to allergic rhinitis.

Tests may not be needed. In some cases, you may have:

• Skin test—Skin testing is one of the easiest ways to find out which allergen may be causing problems for you. A tiny particle is placed under the skin. If there's a reaction, it will happen within 20 minutes. The test is confirmed if the skin becomes raised, red, and itchy.
• RAST blood test—A blood sample will be taken to find how much of a certain antibody is made in the body. This test is used to find out how you respond to allergens. Blood tests are only used when skin tests are not available, unsafe, or will not work.
• Nasal smear—A sample of the inside of your nose may be taken. It can be looked at in a lab to find a cause.
• Nasal endoscopy—A tiny fiberoptic camera may be used to view more deeply inside your nose. This is usually done to see if the you're also having problems with your sinuses.