Definition

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

• Seasonal (sometimes called hay fever or rose fever)—happen at specific times of the year. Common causes are pollens from tree, grass, or weeds.
• Persistent—can happen throughout the 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 is started when the allergen makes contact with the 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.

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Risk Factors

The risk of allergic rhinitis is higher in those with:

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

Symptoms

Allergic rhinitis can cause:

• Sneezing
• Itching in the nose, eyes, throat, and ears
• Red, watery eyes
• Runny nose, nasal congestion
• Congestion with sinus pressure
• Postnasal drip and cough
• Headache
• Dark circles under your 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 to guess 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 in that area becomes red, raised, and itchy.
• RAST testing—A small sample of blood is taken. It will be tested for different allergens.

Treatment

Avoiding the allergens is the best way to treat allergies. Specific steps will depend on the type of allergen, for example:

Reducing dust mite allergens:

• Wash pillows and bed sheets regularly in hot water.
• Remove carpeting, feather pillows, and upholstered furniture, especially in bedroom.
• Keep clothes off bedroom floor.
• Use acaricides solutions to kill dust mites.
• Keep humidity levels < 50%.
• Use double-bag vacuum bags and HEPA filters.

Reducing mold contact:

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

Reducing animal allergens:

• Keep your pet out of your 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 you area. If the allergen level is high:

• Stay indoors and keep windows closed.
• Consider using an air purifier inside.
• Do not dry clothes outside.
• Shower when you get home. Keep clothes that were worn outdoors out of the bedroom.

General steps that may reduce contact with allergen:

• Use petroleum jelly on the nostrils. The jelly may catch some of the allergens before they pass into the nose.
• Nasal filters—Device inserted into the nostrils that can filter allergens before they reach the nose.
• A neti pot, nasal sinus rinse, or saline nasal spray can help flush nasal passage. It may clear irritants and help to loosen congestion.

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

Prevention

There are no steps to prevent the chance of having allergies.