Diagnosis

To evaluate whether you have an allergy, your doctor will likely:

  • Ask detailed questions about signs and symptoms
  • Perform a physical exam
  • Have you keep a detailed diary of symptoms and possible triggers

If you have a food allergy, your doctor will likely:

  • Ask you to keep a detailed diary of the foods you eat
  • Ask if you've stopped eating the suspected food during the allergy evaluation

Your doctor might also recommend one or both of the following tests. However, be aware that these allergy tests can be falsely positive or falsely negative.

  • Skin test. A doctor or nurse will prick your skin and expose you to small amounts of the proteins found in potential allergens. If you're allergic, you'll likely develop a raised bump (hive) at the test location on your skin.
  • Blood test. Specific IgE (sIgE) blood testing, commonly called radioallergosorbent test (RAST) or ImmunoCAP testing, measures the amount of allergy-causing antibodies in your bloodstream, known as immunoglobulin E (IgE) antibodies. A blood sample is sent to a medical laboratory, where it can be tested for evidence of sensitivity to possible allergens.

If your doctor suspects your problems are caused by something other than an allergy, other tests might help identify — or rule out — other medical problems.

Treatment

Allergy treatments include:

  • Allergen avoidance. Your doctor will help you take steps to identify and avoid your allergy triggers. This is generally the most important step in preventing allergic reactions and reducing symptoms.
  • Medications. Depending on your allergy, medications can help reduce your immune system reaction and ease symptoms. Your doctor might suggest over-the-counter or prescription medication in the form of pills or liquid, nasal sprays, or eyedrops.
  • Immunotherapy. For severe allergies or allergies not completely relieved by other treatment, your doctor might recommend allergen immunotherapy. This treatment involves a series of injections of purified allergen extracts, usually given over a period of a few years.

    Another form of immunotherapy is a tablet that's placed under the tongue (sublingual) until it dissolves. Sublingual drugs are used to treat some pollen allergies.

  • Emergency epinephrine. If you have a severe allergy, you might need to carry an emergency epinephrine shot at all times. Given for severe allergic reactions, an epinephrine shot (Auvi-Q, EpiPen, others) can reduce symptoms until you get emergency treatment.

Lifestyle and home remedies

Some allergy symptoms improve with home treatment.

  • Sinus congestion and hay fever symptoms. These often improve with saline nasal irrigation — rinsing out the sinuses with a salt and water solution. You can use a neti pot or a specially designed squeeze bottle to flush out thickened mucus and irritants from your nose. However, improper use of a neti pot or other device can lead to infection.
  • Household airborne allergy symptoms. Reduce your exposure to dust mites or pet dander by frequently washing bedding and stuffed toys in hot water, maintaining low humidity, regularly using a vacuum with a fine filter such as a high-efficiency particulate air (HEPA) filter and replacing carpeting with hard flooring.
  • Mold allergy symptoms. Reduce moisture in damp areas, such as your bath and kitchen, by using ventilation fans and dehumidifiers. Fix leaks inside and outside your home.

Alternative medicine

Clinical practice guidelines suggest that some people with allergic rhinitis may benefit from acupuncture.

Preparing for your appointment

For symptoms that could be caused by an allergy, see your family doctor or general practitioner. You might be referred to a doctor who specializes in treating allergies (allergist).

What you can do

Ask if you should stop taking allergy medications before your appointment, and for how long. For example, antihistamines can affect the results of an allergy skin test.

Make a list of:

  • Your symptoms, including any that seem unrelated to allergies, and when they began
  • Your family's history of allergies and asthma, including specific types of allergies, if you know them
  • All medications, vitamins and other supplements you take, including doses
  • Questions to ask your doctor

Some basic questions to ask your doctor include:

  • What is the most likely cause of my signs and symptoms?
  • Are there other possible causes?
  • Will I need allergy tests?
  • Should I see an allergy specialist?
  • What treatment do you recommend?
  • I have these other health conditions. How can I best manage them together?
  • What emergency symptoms should my friends and family be aware of?

Don't hesitate to ask other questions.

What to expect from your doctor

Your doctor is likely to ask you questions, including:

  • Have you recently had a cold or other respiratory infection?
  • Are your symptoms worse at certain times of the day?
  • Does anything seem to improve or worsen your symptoms?
  • Are your symptoms worse in certain areas of your house or at work?
  • Do you have pets, and do they go into bedrooms?
  • Is there dampness or water damage in your home or workplace?
  • Do you smoke, or are you exposed to secondhand smoke or other pollutants?
  • What treatments have you tried so far? Have they helped?