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Why does it happen?Our noses are designed to warm, moisten, and clean the air we breathe. Each side of the nose contains a slit-like cavity lined with a special skin rich in blood vessels. Warm blood under the surface heats air coming through the nose to body temperature. Glands in the skin release thin mucus. This evaporates to moisten the air and leaves a sticky substance to catch dust particles, like flypaper.
These changes to incoming air protect our lungs. Among the particles in the air are viruses and bacteria that can cause infections. The mucus in the nose catches them and uses immune (defence) system reactions to neutralize them. If one gets through the body’s defences, the lining of the nose swells, makes even more mucus, and creates a head cold. Fever also helps defeat infection. This process takes a few days, then the body returns to normal.
Allergic rhinitis involves an overactive immune system. Allergens trigger the swelling and mucus production response. Allergic triggers are often organic dusts in the air, which may come from:
On the prairies, dry air carries organic dusts a long way, especially when chinook winds are blowing. Different dusts dominate at different times of year. Some people react to only one or a few and get allergic reactions for only a short time each year (seasonal rhinitis). Others react nearly all year round (perennial rhinitis).
An overactive immune system affects more than just the nose. The same skin that lines the nose also lines the sinuses. These air-filled holes in the bones of the head reduce head weight and help the voice resonate. (see diagram oppposite). They also produce the gas nitrous oxide, which seems to help our lungs work better
When nasal passages are inflamed by infection or allergy, so is the skin lining the sinuses. The sinuses also fill with fluid, which cannot escape because the narrow entrances are blocked too. This produces pain in the forehead and cheeks – the feeling of sinusitis. Sometimes sinuses further back in the head, under the brain, become blocked. It can be hard to distinguish the resulting heaaches at the top or back of the head, or on one side, from migraines.
The Eustachian tubes lead from each ear to the back of the nose. They allow air to fill the ear cavity, so the middle ear works properly. The same special skin lines the Eustachian tubes and ear cavities. They can also fill with fluid and become blocked, leading to feelings of pressure in the ears.
Allergic noses and asthma both have similar reactions, occurring in different parts of the air passages. They often occur together in the same person or in families.
The body’s allergic reaction makes us sneeze and feel itchy. Fluid runs from the nose. Swollen skin and thick fluid block breathing. If the reaction is minor, the fluid may dry to form crusts inside the nose. These are irritating, but removing them by picking the nose can cause nosebleeds. Sometimes the nose gets itchy. Children often rub their nose, in what we call the ‘allergic salute’. This often leaves a little crease across the nose just above the tip.
Many allergy sufferers breathe through the mouth. At night when we relax in sleep, the natural instinct is to breathe through the nose. The mouth then closes. Many people with allergic blocked nose wake up short of breath, then go back to sleep again after breathing through their mouth. This cycle of sleeping and waking disturbs sleep and is a type of sleep apnea. So, allergies can cause sleep apnea or make it worse.
Many people also have an allergic response in their eyes. They get swelling and reddening of the conjunctiva (skin over the white of the eye and on the back of the eyelids).
Allergic rhinitis can range from seasonal stuffiness, lasting a few weeks or months, to chronic year-round blockage and sinusitis. Sometimes it appears simply as a long cold, taking a few weeks to taper off each time. However, there is none of the fever that would indicate infection. Allergy symptoms may simply be an irritating cough with mucus in the back of the nose and throat, the so-called ‘post-nasal drip’ or ‘upper airway cough syndrome’.
A blocked nose or cough lasting more than a couple of weeks may be an allergic response, especially in those who also have asthma.
Sadly, there is no clear test to diagnose allergic rhinitis. Often the only way to diagnose it is to try treating it.
Treatment Interrupting the cause and treating symptoms are the main ways to deal with allergic rhinitis.
If possible, finding and reducing exposure to the cause is the best treatment. This works best when the cause is very specific. For instance, those who are allergic to cats or other certain animals can stay away from them. Keeping windows closed and using a highly efficient filter in the home air system can also reduce external dust problems.
Allergy injections can suppress the body’s reaction. However, this requires special diagnosis. Then, a serum must be developed and injected regularly for a long time. Some people find this very effective, especially for specific allergies. Others feel injections are more trouble than they are worth.
The table to the right shows the anti-allergy drugs readily available.
Antihistamine tablets are usually the first drugs used to treat allergic rhinitis. Older, less expensive types have decongestant action as well, so may work better. They may cause sleepiness, and so are best used at night. Newer types cause less sleepiness, and are good for use in the daytime. However, they cost more. These drugs can be bought without a prescription at a pharmacy.
Nasal sprays of surface-acting cortisone (steroid) drugs often help. As very little is absorbed, they are safe to use long-term at the usual dosage. These are prescription drugs, and more expensive than antihistamines. They are often only partly covered by drug plans. Steroid nasal sprays need to be used regularly for maximum benefit.
Cromoglycarte sprays may also be helpful, but they are short acting, so need to be used every few hours.
For eye allergy, eye drops of cromoglycate often help. Since this only lasts a short time, they must be used four times daily. Antihistamine eye drops like olopatadine, a prescription medication, are also useful for eye allergies.
These treatments can be used all the time by those with chronic allergies, or just when needed by those with seasonal allergies or continuing reactions to an infection. Using them regularly for at least a week may increase the effect.
While decongestants are useful for head colds, avoid using them for long-lasting problems like allergies. Decongestants come in as tablets containing pseudoephedrine, or as nasal sprays containing a variety of drugs.
Pseudoephedrine is related to the amphetamine group of drugs. It causes wakefulness and may increase blood pressure. The heart may also beat rapidly, especially in older people or those with heart disease or high blood pressure. In most provinces you must ask the pharmacist for pseudoephedrine products, since they are now kept behind the counter.
Decongestant nasal sprays work quickly but can create problems. After a few days, the sprays create a rebound effect that makes the original problem worse and need even more treatment. Using decongestant nasal sprays is not recommended for more than three days in a row.
Combination medication products
Pharmacy shelves hold many combination (all-in-one) products, which contain ingredients for more than one symptom. They usually contain variou combinations of an antihistamines, a decongestants, a pain reliever like acetaminophen or ibuprofen, and sometimes a cough medication, such as dextromethorphan (DM). These combinations are often effective as they treat a variety of symptoms all at once. However, choosing a combination product may mean you are taking some medicines to treat symptoms that you do not have. Any ingredient can cause side effects, even the ones you do not need. Since the same trade name is sometimes used for packages containing different combinations, read the small print carefully to see what you are getting. Remember too that combining combination products with other over-the-counter medications may double up on some ingredients.
Start by identifying what your specific symptoms are, then work out the best way to treat them. Often you can buy individual drugs, perhaps generic versions, at a much lower price than a combination product. If you are not sure which over-the-counter product to use, you can ask your pharmacist or your doctor for advice.
Bacteria live both on the skin and inside the nose. These are adapted to living on human surfaces and seldom cause disease. Still, when we produce lots of fluid the bacteria can grow, especially in the sinuses or ear cavities where fluid cannot drain easily. When bacteria do grow, the body often reacts with leucocytes, cells that fight infection. When they die in the fight, they release coloured compounds that make mucus yellow or green.
Many people ask their doctors for antibiotics to treat sinus pain. These can help if there is a bacterial infection present. However, it is usually better to treat the underlying cause, most often allergy. Vigorous allergy treatment usually solves the problem without using (and overusing) antibiotics.
In extreme cases, sinus surgery is useful. However, it cannot stop the basic allergic reaction. Drug management is usually still needed.
Allergic rhinitis, while common and annoying, is treatable. Learn the signs and triggers that affect you, and treat them with the help of your family doctor and pharmacist.
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