Definition

Allergic rhinitis is the set of symptoms that occurs when you breathe in substances you are allergic to. These substances are called allergens.

  • Seasonal (intermittent) allergic rhinitis—Sometimes called hay fever or rose fever. This condition occurs during times of the year when allergens are in the air. Spring and Fall are the most common times. The most common allergen is pollen.
  • Perennial (persistent) allergic rhinitis—This condition is caused by allergens such as chemicals, dust, dust mites, cockroaches, animal dander, mold spores, or, occasionally, foods. It may occur any time of year that you encounter these allergens.

Causes

An allergic reaction occurs when your body's immune system overreacts to an allergen. When you breathe in an allergen, cells in your nasal passages make a chemical called histamine. Histamine causes your nose to feel itchy and also causes swelling and mucus production in the nasal passages.

Site of Histamine Production

Nasal passage

This area has swelling and increased mucus production after contact with an allergen.

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Risk Factors

A risk factor is something that increases your chance of getting a disease or condition. Some risk factors include:

Symptoms

Allergic rhinitis can cause the following symptoms:

  • Sneezing
  • Itching in the nose, eyes, throat, ears
  • Red, watery eyes
  • Runny nose, nasal congestion
  • Sinus pressure
  • Postnasal drip and cough
  • Headache
  • Dark circles under your eyes

Diagnosis

Your doctor will try to find out which allergens you are allergic to. You may be referred you to an allergist, if necessary.

Tests may include:

Skin Prick Test

A tiny bit of an allergen is placed under the skin with a needle. The doctor watches to see if the skin in that area becomes raised or irritated. This can be done for multiple allergens at the same time.

RAST Testing

A small sample of blood is taken and tested for different allergens.

Provocation Testing

You breathe in air containing an allergen. The doctor will watch to see if you have an allergic reaction, such as wheezing or trouble breathing.

Treatment

The most effective way to treat allergies is to avoid the allergen. Since this can sometimes be difficult or impossible, other treatments are available.

Treatments may include:

Medications

  • Antihistamines—stop or reduce the production of histamine, usually taken as pills
  • Decongestants—decrease congestion by constricting blood vessels, taken as pills or as a nasal spray
  • Mast cell inhibitors—nasal sprays that interfere with the chemical reactions leading to histamine release
  • Topical corticosteroids—nasal sprays that decrease swelling in the nasal passages

Immunotherapy (Allergy Shots)

Very small amounts of allergens are injected over weeks, months, or even years. The goal is to make your body's immune system less sensitive to those allergens.

It may be possible to perform this therapy by placing allergens under the tongue (sublingual). In a recent study, adult patients allergic to a certain grass pollen modestly reduced their symptoms by taking grass allergen tablets sublingually every day for 18 weeks. * Further study is needed.

Prevention

The following strategies may help prevent allergic rhinitis:

  • Stay inside during the morning hours when pollen counts are highest
  • Avoid outside activities during the time of year when the trees, flowers, or molds to which you are allergic are blooming
  • Keep the windows of your house and car closed to keep pollen out
  • Use an air conditioner to reduce indoor humidity during the warmer months to prevent mold and mildew growth
  • Clean your air conditioner's filters regularly
  • Consider running an air purifier in your home, especially in your bedroom
  • Use vacuum cleaners and air conditioners with HEPA filters to trap allergens
  • Decrease or avoid outdoor activities on hot summer days, when ozone levels may exacerbate allergies
  • Cover pillows and mattresses with vinyl covers to reduce your exposure to dust mites
  • Wash bedding weekly in very hot water
  • Use fewer dust-collecting items such as curtains, bed skirts, carpeting, and stuffed animals, especially in your bedroom
  • If you can't avoid having a furry pet, vacuum frequently, keep your pet out of bedrooms and other rooms with carpets