Allergic Rhinitis

Definition

Allergic rhinitis is swelling in the nose after contact with allergens. An allergen is anything that causes an abnormal immune system response. There are 2 main types:

• Seasonal—happens at certain times of the year. Common causes are pollens from trees, grass, or weeds. This is sometimes called hay fever or rose fever.
• Perennial—can happen all year. Common causes are chemicals, dust, dust mites, cockroaches, animal dander, or mold spores.

Causes

An allergic reaction is an overreaction of the immune system. A chain of events starts when the allergen gets inside of the nose. Immune cells in the nose release a chemical called histamine. Histamine causes itchiness and swelling. It also increases the amount of mucus in the nose.

Site of Histamine Production.

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Risk Factors

The risk of allergic rhinitis is higher in people who have:

• Family members with allergic rhinitis, eczema, or asthma
• Eczema
• Asthma
• Food allergies

Symptoms

A person with allergic rhinitis can have:

• Sneezing
• Itching in the nose, eyes, throat, and ears
• Red, watery eyes
• Runny or stuffy nose
• A feeling of pressure in the nose or behind the cheeks
• Mucus dripping from the back of the nose into the throat
• Cough
• Headache
• Dark circles under the eyes

Diagnosis

The doctor will ask about symptoms and past health. Allergic rhinitis may be suspected based on symptoms. Tests may be done to see what allergens are causing problems. The time of year and location may also help figure out the allergen. Tests may include:

• Skin prick test—A tiny bit of an allergen is placed under the skin. The doctor watches to see if the skin near it turns red or becomes raised and itchy.
• Specific immunoglobulin E (IgE) testing—A small blood sample is taken to be tested for allergens.

Treatment

The goal of treatment is to get rid of the symptoms. Avoiding the allergens is the best way to do that. How to avoid an allergen depends on what it is.

To reduce dust mite allergens:

• Wash pillows and bed sheets regularly in hot water.
• Get rid of carpeting, feather pillows, and furniture covered in fabric, especially in bedrooms.
• Keep clothes off the floor.
• Use acaricides solutions to kill dust mites.
• Keep humidity levels in the home under 50%.
• Use double-bag vacuum bags and HEPA filters.

To reduce mold contact:

• Wear face masks when working with soil, leaves, or compost.
• Try to avoid moist, damp areas in the home.
• Use a dehumidifier in damp places like basements.
• Fix leaky roofs or pipes.

To reduce animal allergens:

• Keep pets out of the bedroom and off of furniture.
• Vacuum often or remove rugs.
• The pet may need to be removed for severe allergens. It may take 4 to 6 months to clear the home of pet allergens.

Use news reports or online resources to track pollen levels in the area. If the allergen level is high:

• Stay indoors and keep windows closed.
• Think about using an air purifier inside. Use the car air filter instead of driving with the windows down. Be sure to clean both filters regularly.
• Do not dry clothes outside.
• Shower when returning home. Keep clothes that were worn outdoors out of the bedroom.

Other steps that may reduce contact with allergen:

• Use petroleum jelly on the nostrils. The jelly may catch some of the allergens before they get into the nose.
• Nasal filters—Device inserted into the nostrils that can filter allergens before they reach the nose.
• Face masks that cover the mouth and nose. These can help for short periods of time:
  • Outdoors during pollen season
  • With exposure to allergens at work or other places
• A neti pot, nasal sinus rinse, or saline nasal spray can help flush nasal passages. It may clear irritants and help loosen congestion.

It is not always possible to avoid all allergens. Other treatments may help reduce the body's reaction to an allergen:

Prevention

Allergies cannot be prevented.