Every time we breathe in, we inhale countless numbers of small particles of dust, smoke, pollen and animal fluff etc. Most of us do not suffer any bad effects from this, but for many people, some of these particles can set off an allergic reaction. The result can be itchy, running nose and eyes, sneezing, a blocked nose, an itchy palate and other problems. This is called allergic rhinitis. Rhinitis means inflammation of the lining of the nose.
More females than males develop allergic rhinitis but over all about 1 out of every 5 people have significant symptoms. There are a lot of factors involved including the environment, occupation, stress and diet. It does run in families to a certain extent. Usually the symptoms improve as the person gets older, and it is rare for allergic rhinitis to develop for the first time in someone over 40 years of age.
Some people have their symptoms at a particular time of the year, usually in spring and early summer when pollen is plentiful. This type of seasonal allergic rhinitis is often termed hay fever. In other people, their allergic rhinitis symptoms may occur all year round (perennial allergic rhinitis).
Substances which trigger an allergic reaction are called allergens. Most allergens are inhaled but it may be possible that an allergen taken in by eating, for instance, can also set off allergic rhinitis. Pollen usually triggers seasonal allergic rhinitis. Other substances can set off symptoms all year round e.g house dust mites, animal dander (especially cats and dogs), fungal spores and some foodstuffs.
Skin prick testing can help identify some allergens. Blood testing (RAST) may also be useful, but none of the tests are completely accurate. Treatement of Allergic Rhinitis
The treatment of allergic rhinitis has 4 components:
Avoidance of Allergen
Avoid the allergen trigger as much as possible. If you have hay fever, avoid forests, bush or grassy areas when pollen concentrations are high. There will be less pollen inside a house than outside. Keep your environment as dust free as possible and avoid any other possible irritants such as cigarette smoke, perfumes, rapid changes in temperature etc. Rarely a permanent change of job or place or residence is necessary.
Those with all year round allergic rhinitis may benefit from all the above suggestions. If dust mite is a trigger, concentrate on keeping dust levels down e.g by dusting with a damp cloth every few days. The highest concentration of dust mites are found in the bedroom and particularly in the bed itself. The mattress is a particular problem because even regular vacuuming removes only a small percentage of the mite allergens inside.
Plastic covers are made in New Zealand from treated polycotton fabric, which allows the fabric to breathe and yet provides a barrier to dust mites and their allergens. Choose synthetic fabrics in preference to wool or cotton fabrics. Feather and cotton stuffed toys should be removed from the bedroom. Indispensable favourite toys can be brushed and then frozen in the deep freeze for 24 hours every other day to keep allergen levels to a minimum.
Be sure that mould cannot collect anywhere. A dehumidifier for damp areas in the house may help to reduce the mould levels and can be useful for people allergic to fungal agents. Discuss with your doctor whether your pet is a possible cause of your problems.
Medications
These can help and your doctor will choose from the following:
Corticosteroid nasal sprays reduce inflammation in the area and are the mainstay of treatment of allergic rhinitis. If used continuously, they can improve symptoms for several months. However you must take them all the time not just when you have the symptoms if they are going to helop. These sprays affect the nose only – they do not have any other effect on the rest of the body and are safe for pregnant women at normal dose levels. The aqueous, rather than the aerosol spray, is kinder on the nose. Poorly controlled allergic rhinitis leaves the lining irritable. Non-allergic irritants may then react with the oversensitive lining, causing allergy like symptoms. This is one reason why cigarette smoke, perfumes, petrol fumes and air conditioning cause symptoms for some people. Adequate treatment with a steroid nasal spray reduces this risk.
Antihistamines help block part of the allergic process, but not all of it. They can be very useful, but in some patients they have the side effect of making them feel quite sleepy. This is less of a problem with the newer antihistamines such as Telfast, Claratyne and Zyrtec. Antihistamine nasal sprays may also be helpful. Sodium chromoglycolate may help some patients, especially if they have eye symptoms.
Surgery
Surgery is of limited benefit in the treatment of allergic rhinitis. It is used only to relieve nasal obstruction which helps improve the delivery of corticosteroid nasal sprays or to treat the complications of allergic rhinitis, in particular chronic sinusitis. Cautery or surgical reduction of the turbinates and/or correction of a deviated nasal septum can help reduce the obstruction and secondarily improve the effect from nasal sprays. If there are nasal polyps, a deviated septum and/or underlying sinus disease, then surgical treatment of these conditions can help improve the effect of anti-allergy treatments.
Immunotherapy
Immunotherapy (Desensitisation) can be useful for some patients who are sensitive to grass/pollen and/or dust mites. The treatment programme involves 3 years of injections and is only suitable for selected patients where nothing else has been helpful. Patients need to be prepared to undergo the whole programme.
Oral desensitisation programmes are now available for some allergens but are expensive.