Allergic Rhinitis - Some Facts

What is allergic rhinitis
Rhinitis describes the lining of the nose when it becomes red and swollen (inflamed). People with this condition usually complain of an itchy, stuffy or drippy nose, a scratchy throat and coughing.

The nose makes a thin, clear, liquid called mucus. This mucus is located on the inside lining of the nose. Its purpose is to help trap such things as dust, germs, pollen etc., preventing them fom entering the lungs. This thin mucus, along with the waste normally drains down the back of the throat and into the stomach. It is usually in such small amounts that it goes unnoticed and causes no harm to the body.

When the inside of the nose becomes inflamed, it creates more mucus. The increased amount of mucus often becomes thicker and pale yellow in colour. It also becomes more noticeable as it drains down the throat (postnasal drip), causing coughing. Some of this extra mucus may also drain out of the front of the nose.

What Causes Allergic Rhinitis
Rhinitis can be cuased by any number of different things that irritate the lining of the nose. In response to this irritation, cells that are responsible for reaction to irritation (inflammatory cells) release a number of chemicals, the most important being histamine. Histamine is responsible for the watery, itchy eyes, runny nose and sneezing of rhinitis.

Other inflammatory cells, which include eosinophils, basophils, macrophages and neutrophils, also play a role in the chronic stages of the allergic response. These inflammatory cells release chemicals such as leukotrienes etc. which cause nasal obstruction and further increase mucus secretions.

Allergic Rhinitis is caused by substances known as allergens. Some allergens are only a problem during certain times of the year (seasonal). Common seasonal allergens include molds and pollens. Seasonal allergic rhinitis is often called hay fever and usually occurs during spring or fall.

Other allergens can be a problem anytime of the year and sometimes lasts throughout the year (perennial). Common perennial allergens include dust mites, molds, animal dender, insect debris, smoke, fumes and chemicals.

Recognising the Symptoms
Common symptoms of allergic rhinitis incluse:
-red, watery, itchy eyes
-runny nose (rhinorrhoea), itchy nose
-stuffiness (congestion) in the nose and ears
-sneezing (usually sudden and strong)
-a scratchy throat, coughing due to postnasal drip
-dark circles under the eyes (allergic shiner)
-breathing through the mouth
-loss of, or change in, sense of smell
-headache

Complications
-difficult in sleeping
-sinusitis: infection of the sinuses
-otitis media: infection of the middle ear
-epistaxis: nose bleed
-conjunctivitis: inflammation of the conjunctiva

In addition, conditions such as nasal polyps (small growth of tissue), asthma or sleep apnoea (interupted breathing during sleep) may also be associated with rhinitis.

Conditions Associated with Allergic Rhinitis
Otitis Media
Sleep apnoea
Asthma
Sinusitis
Nasal polyps
Epistaxis

Diagnosing Rhinitis
The symptoms of alergic rhinitis are usually temporary, but if they last more than 3 to 4 days or occur frequently, possible causes need to be looked for. The diagnosis is based on:
-history of the allergic symptoms
-diagnostic test to detect certain antibody responsible for allergy e.g. IgE
-skin test to identify possible allergens
-nasal challenge test to identify pollutants

Treatment
Allergic rhinitis usualy cannot be cured. The aim of treatment is to prevent or reduce the symptoms.

Medication
1. Antihistamines
used for both preventing and treating reactions to allergens.

2. Cromolyn Sodium
used to prevent reactions. Prevents the body from releasing chemicals such as histamines when triggered by allergens.

3. Decongestants
Decreases swelling of nasal lining. Use not more than 3 days!

4. Ipratrobium Bromide
Decreases secretion caused by release of histamine

5. Nasal wetting Spray
relieve nasal irritation. Help loosen and remove thick and dried mucus.

6. Sterod nasal spray
reduce the body's response to allergens and decrease inflammation. Can take days to weeks to see its effect.