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  • Allergies

An allergy is an adverse reaction by your immune system to contact with a substance which for most people is harmless. There are many types of allergies affecting different parts of the body. For many people, the allergy affects their nose and eyes. What triggers this allergic response? It is often nothing more than a few grains of pollen or a scattering of house dust in the air. So small, you might need a microscope to see them; and usually so harmless that most people are unaware of their presence. Yet to a growing percentage of the population, these tiny flecks floating unnoticed in the air are allergy triggers (known as allergens) and the people who react to them are suffering from an airborne allergy, also known as allergic rhinitis. There are other forms of allergy such as asthma, skin allergies and food allergies.
what causes airborne allergies?
All of us are exposed to different potential allergens throughout the day. Where you are when sneezing starts, as well as the time of day, can provide clues to identify the cause. For example, if you suffer from airborne allergy symptoms when you are out in countryside then pollen is most likely a trigger. If this affects you for a large part of the spring and summer, then you may be allergic to more than one type of pollen. There are several triggers that can affect you in the garden. Mowing the lawn throws grass pollen into the air, digging or potting out plants can release mould spores from the soil.


If you have airborne allergy symptoms at about the same time each year, then the chances are you have hayfever and are sensitive to pollen or mould spores. The time of year might give you a good indication of which types of pollen are causing the problem. Hayfever seasons vary from year to year depending on the weather.

mould spores

Moulds and fungi reproduce by sending out spores into the air. About 20% of people who suffer from airborne allergies are affected by mould spores. Moulds can grow anywhere, indoors and out. They prefer damp conditions - the kitchen and bathroom, in wooden window frames, the soil of houseplants and under wallpaper. Outside, there are plenty of moulds in the soil, in rotting wood and leaves, grass cuttings and compost heaps.

house dust mites

It's actually not dust that causes the problem, but a tiny creature called the house dust mite. House dust mites are almost always present in house dust, even in the most clean and tidy homes. In some ways they serve a useful purpose in disposing of skin flakes in house dust. They mostly like damp and dusty spots found somewhere in nearly every home. The house dust mite or, in fact, its droppings, are the most common trigger of airborne allergy.


pets (dander)

It is often not the fur itself that causes the allergy problem. Dander, the mixture of small particles of fur, skin scales (like dandruff) and saliva is the actual cause. Cats, in particular, cause allergies but dogs and rabbits can also trigger the itching and sneezing of airborne allergy. Because cats groom themselves so thoroughly, the saliva finds it way onto carpets, furniture and other surfaces.

other triggers

In addition to these common allergy triggers there are others that can make life difficult for airborne allergy sufferers.

Air pollution

High concentrations of nitrogen dioxide, sulphur dioxide and other chemicals that find their way into the atmosphere can irritate the nose and airways even in those who do not suffer from airborne allergy.

Air-conditioned atmospheres
Air conditioned atmostpheres that suck chemicals, dust and pollution from outside, can make allergic reactions worse. Chemicals, pollution from outside, changes in temperature, low humidity and other factors in the 'sick building syndrome' can increase nasal sensitivity. Even good air conditioning, with efficient air filters that can reduce the level of pollen, will not get rid of all air pollution.
  • Runny nose
  • Sneezing
  • Itchy nose
  • Blocked nose
  • Congestion
  • Itchy eyes
  • Watery eyes
  • Pressure around the eyes and sinuses
available treatments
There are several drug treatments available for airborne allergies. These can be used on their own or in combination to provide a range of relief from the distressing symptoms of an airborne allergy:

Anti-Inflammatory Nasal Sprays
The body manufactures a natural anti-inflammatory substance called cortisol. The corticosteroids used in nasal sprays are based on this natural substance but are chemically modified to make them more suitable for treating airborne allergy.

They are very effective so only tiny doses are needed. They are designed to be metabolised quickly. This means that, after they have done their work in the nose, the body quickly breaks them down into inactive substances.

When applied directly to the nose where allergic reactions start, anti-inflammatory nasal sprays are highly effective and have few side effects. Apart from a chemical similarity, the anti-inflammatory nasal sprays used to treat airborne allergies have no connection with other sorts of steroids.

Other treatments are not as effective in relieving symptoms in the nose. Because they act at several points in the allergic process, antiinflammatory nasal sprays relieve more of the symptoms of hayfever and airborne allergies.

Anti-inflammatory nasal sprays are recommended as first line treatment for airborne allergies and can be purchased over the counter from a pharmacy. Anti-inflammatory nasal sprays work best when they have the opportunity to stop the build-up of inflammation in the nose.

Antihistamines work best to control symptoms that are a direct result of histamine release - sneezing, runny and itchy nose. However, other parts of the allergic process are not directly related to histamine. Antihistamines, therefore, are less effective than some other treatments in controlling nasal congestion and the blocked-up, groggy feeling. Older types of antihistamines can cause drowsiness in some people. This can be an advantage if the allergy is disturbing sleep. Doctors usually use newer non-sedating antihistamines for most people now. Antihistamines can be bought over-the-counter from a pharmacy.

Anti-allergic eye drops
Cromones such as cromoglycate and nedocromil stabilise mast cells (which release histamine and other chemicals during an allergic reaction), reduce the release of histamine that follows an allergic reaction. Eye drops can relieve the symptoms of itchy eyes and are used as preventative medication. Cromones have a good safety profile and are suitable for young children or pregnant women. Overall, these medicines are less effective than antihistamines and anti-inflammatory nasal sprays. Nevertheless, cromone eye drops are very useful for protecting against itchy eyes. They only last a short time and need to be used several times a day.

Desensitising Injections
Repeated exposure to whatever causes the allergy can ease the reaction. It's like being vaccinated against an allergy. This treatment is usually for the most severe cases when recommended by your GP.
When to consult your doctor
If over-the-counter remedies don't help, see your doctor who may refer you to an allergy specialist who will be able to find out what's causing your allergy and recommend suitable treatment.

If your symptoms are having a serious effect on your day-to-day life, consult your doctor. Also if you are experiencing chesty symptoms such as wheezing you should see your doctor to make sure that you don't have asthma.