Tests for Allergic Rhinitis

When you experience nasal symptoms that last longer than two weeks and tend to recur, you should consider making an appointment with your doctor for a complete medical evaluation.

Before your appointment, you should keep a diary of your symptoms. In many cases, your condition can be diagnosed by your medical history and a physical examination alone.

The season in which your symptoms occur will narrow the list of possible causes. Your doctor may wish to perform skin testing to determine which allergens are causing your symptoms. A blood test (RAST) can be obtained as an alternative, but this is not as sensitive as skin testing.

Because hay fever often is associated with asthma, tests to rule out this condition may be conducted as well. Asthma refers specifically to a reaction in the airways that frequently but not always involves an allergy. The majority of adults with asthma, and an even larger majority of asthmatic children, have an allergy to one or more substances.

Questions your doctor might ask when taking a medical history:

16 questions your doctor might ask:

1. What type of symptoms do you have?
2. How long have you had these symptoms?
3. When symptoms occur, how long do they last?
4. Are your symptoms seasonal (come and go throughout the year),or do they last year-round?
5. Do your symptoms occur when you are outdoors or indoors?
6. Do your symptoms get worse when you are around pets? Do you have any pets?
7. Do you smoke? Does anyone in your family smoke?
8. Are your symptoms interfering with your daily activities or interrupting your sleep?
9. What makes your symptoms better? What types of treatments have you tried?
10. What medication(s) are you taking now for symptom relief? Do these medications provide relief? Do they cause drowsiness?
11. What other medications are you taking, including prescription, over-the-counter, vitamins, and herbal supplements?
12. What type of heating system do you have? Do you have central air conditioning?
13. Do you have any other health conditions, such as asthma or high blood pressure?
14. Are you having difficulty with your sense of smell or taste?
15. What makes your symptoms worse? Better?
16. How much can you modify your lifestyle to reduce your exposure to these allergens?

Questions to ask your doctor:

11 questions to ask your doctor about allergies: 

1. What substances are causing my allergies?
2. What allergy symptoms should I be concerned about? When is it necessary to call the doctor?
3. What allergy medications or other treatments are available? What are the benefits and side effects of each treatment?
4. Am I a candidate for allergy shots (allergen immunotherapy)?
5. What guidelines should I follow if I'm prescribed allergy medication?
6. Should I take medicine all the time or only when my allergy symptoms worsen?
7. Should I stop exercising outside if I have allergies?
8. How can I avoid or reduce exposure to certain allergens?
9. What can I do around my house to reduce exposure to allergens?
10. Should I avoid going outside during certain times of the day?
11. How often should I come in for follow-up appointments?

Skin tests

An allergy skin test is used to identify the substances that are causing your allergy symptoms. It involves applying an extract of an allergen to your skin, scratching or pricking the skin to allow exposure, and then evaluating the skin's reaction.

What to expect: First, a doctor or nurse will examine the skin on your forearm and clean it with alcohol. (Sometimes, this test is performed on an area of the back.) Areas on your skin are then marked with a pen to identify each of the allergens that will be tested. A drop of an extract made from each allergen--such as pollen, animal dander, or mold spore--is placed on the corresponding mark on your skin. A small disposable pricking device is then used to ensure that the extract enters the outer layer of the skin, called the epidermis. The skin prick is not a shot and doesn't cause bleeding. Sometimes, instead of the skin-pricking method, a small amount of the allergen is injected just under the skin.

The areas of the skin that become red and itchy indicate the substances that trigger a defensive response by your immune system. The skin reaction may be itchy, but most people say it doesn't hurt much.

After the test, the extracts and ink marks will be cleaned off your skin with alcohol. A mild cortisone cream will be applied to your arm (or back) to relieve any itching that may occur at the sites of the skin pricks. Keep the tested area on your arm uncovered when you go home. Your doctor or allergist will use the results of the test to help develop a management plan for you.

To prepare for the test: Antihistamines block the action of histamine and interfere with the skin test response. For this reason, antihistamine medication should not be taken for at least 48 to 72 hours before skin testing is performed.

Your doctor will give you a list of medications to avoid before the test, since there are other medications (such as tricyclic antidepressants) that will interfere with the test. However, medications being taken for other conditions such as thyroid disorder, high blood pressure, or asthma do not need to be suspended. Give the healthcare provider who is going to perform the skin test a list of all the medications you are taking, including over-the-counter ones. Talk to your doctor about discontinuing your medications prior to the test.