Allergic Rhinitis

It is a condition whereby the symptoms such as sneezing, running nose, nasal itchiness and obstruction arise as a result of a hypersensitivity response of the nose to materials called allergens.
Common allergens include pollen, dust, house dust mite, animal danders (cat, dog, rodent, horse) and mould.

Sometimes change in environmental conditions such as temperature and humidity can cause the same symptom. Very rarely, particular food substance is the culprit but it is very difficult to prove.

An experienced Ear, Nose and Throat specialist can usually make the diagnosis by taking a detail history and physical examination.
Certain blood test such as allergen specific IgE antibody and the skin prick test can determine what substance a patient is allergic to.

Do not keep pets such as dog and cat at home. If you already have one and cannot give it away, try to avoid close contact. Keep it away from the living room and bedroom.
Avoid fuzzy or furry toys or clothing.
Do not carpet the floor.
Change the linen and pillow case frequently (twice a week) and wash them in hot water (>60 degree Celsius). There are also special anti-dust mite cover for the mattress and pillow available commercially.
Keep the house dry, clean and adequately ventilated.
Clean the curtain and upholstery frequently.
Avoid prolonged stay in dusty and polluted areas.

1. Antihistamines:

Reduce nasal discharge, itchiness and sneezing.
The older ones usually cause drowsiness and dry mouth. Newer generation antihistamines are usually less sedating. But a couple of these can cause disturbance of the cardiac rhythm when taken together with an antibiotic called erythromycin.
Now topical form (nasal spray) is available.

2. Decongestants:

These drugs can cause shrinkage of the nasal mucosa by constricting the blood vessel inside and thus relief obstruction.
Oral and topical form available.
The topical form usually acts quickly within minutes. However, prolonged use for few weeks may cause a 'rebound phenomenon'- the nasal mucosa will swell up quickly if the nosedrop is stopped. It is advisable to stop the nosedrop for one day after using it for two days consecutively.

3. Corticosteroids:

More effective than antihistamines in reducing symptoms.
However, if the oral form is taken for a prolonged period of time (more than three to four weeks), serious complications may occur. But few days of treatment are perfectly safe.
The nasal form is safe for prolonged use. Many patients have used it continuously for over a year without side effect. Some preparations are also shown to be safe for use in children as young as 4 years old.
The topical form's action is slower than antihistamines and decongestants. It usually takes few days to act. It is necessary to use it continuously at least for one week or more to gain significant benefit.

1. Will allergic rhinitis regress when the child gets older?

No. Unlike asthma, allergic rhinitis usually remains the same as the child grows older.

2. Many doctors say that allergic rhinitis is not curable. Does it mean that a patient has to take drugs forever?

At present there is no treatment that can change the allergic tendency within a patient. But the symptoms can be adequately controlled with medications. For most patients, few weeks of appropriate treatment can usually completely control the symptoms and all medications can be stopped. Very often, a symptom-free period of six months to one year will follow.

3. Is there any surgery for allergic rhinitis?

Surgical procedures are necessary when certain complications or concomitant conditions present. These include sinusitis not relieved by medications, nasal polyps, enlarged turbinates and deviated nasal septum causing severe nasal obstruction. Very often after the operation symptoms such as nasal discharge, itchiness and sneezing have to be controlled by medication.

***These are general principle only. Individual case should better be interpreted by the doctor consulted.

by Dr. Lo Kwok Fai