Allergic rhinitis, commonly called hay fever, is similar to asthma except in one respect. In asthma, an airborne substance causes an allergic, or hypersensitive, reaction in your lungs and chest. In allergic rhinitis, the reaction occurs in your eyes, nose, and throat. Exposure to an airborne irritant known as the allergen triggers the release of histamine, a body chemical. The release of this substance causes inflammation and fluid production in the fragile lining of the nasal passage, the sinuses, and the eyelids and surface layer of the eyes.

Nobody knows why some people are allergic to otherwise harmless pollen grains or other airborne particles. Presumably, there is a difference in some people’s natural immune systems . Since allergic based diseases such as asthma, contact dermatitis and allergic rhinitis often run in families, the cause is probably partly genetic.

If you have allergic rhinitis, you react to specific allergens. For example, if you have hay fever, the most familiar variety of the disease, you may be sensitive to grass pollen, which is abundant in early summer, to tree pollen, which is in the air in spring, or to ragweed, which blooms in the fall.

In addition to pollen, almost any airborne substance derived from a living organism can cause allergic rhinitis, including bits of animal skin, hair, and feathers. You may also be allergic to house dust or, to be more precise, to the mites that infest the dust.

There are two types of allergic rhinitis, seasonal and perennial. Seasonal allergic rhinitis only bothers you part of the year because it is an allergy to a substance that is not in the air year round. Perennial allergic rhinitis occurs all year round because it is caused by exposure to airborne allergens that may be present at any time.

What are the Symptoms?

If you have allergic rhinitis, you sneeze frequently, your nose runs, and your eyes are red, itchy, and watery. If you rub your eyes, it makes them worse. Itchy skin, dry throat, and wheezing can also occur. If you have hay fever, the symptoms are most severe when there is a lot of pollen in the air. Symptoms tend to be especially severe for 15 to 30 minute periods. These brief periods of acute symptoms are called allergy attacks.

Because airborne allergens are generally too small to see, it is difficult to predict when, or even why, you may have an attack. For example, if you are allergic to cat hair, you may start to sneeze on entering an empty room, because invisible bits of hair from a recent feline occupant are still in the air.

Allergic rhinitis is very common. Although there is a widespread belief that allergic rhinitis is a childhood disorder that you out­grow in your late teens or early twenties, this is not necessarily so. You can develop the disorder at any age, and later recover. You are particularly susceptible, however, if you are under 40 and have another allergic condition such as asthma or dermatitis, or if other members of your family have similar disorders. Many people react to more than one allergen, and some people have both seasonal and perennial bouts of allergic rhinitis.

What are the Risks?

This disorder does not usually endanger your general health.

What should be done?

If you find that allergic rhinitis interferes with your daily routine, see your physician, who will probably first ask questions to find out how serious the problem is for you. The doctor may advise you against professional treatment, because the possible side effects and the inconvenience of some kinds of treatment may cause more problems than the condition itself. If you do not know what causes your allergic rhinitis, your physician may suggest skin tests to find out which allergens make you react. The physician scratches the skin on your forearm and puts drops of liquid that contain a common allergen on the same spot. If the skin under any of the drops turns red and itchy, you are allergic to the allergen in that drop.

What is the Treatment?

Self-help: If you get hay fever regularly, stay indoors as much as possible during the hay fever season, especially when the news media reports a high pollen count. You should avoid wearing contact lenses, because they can increase eye irritation. Resist the temptation to rub your eyes. If your allergic rhinitis is perennial rather than seasonal, try to find out what you are allergic to, and take steps to avoid it or minimize your exposure to it. Self-help recommendations for asthmatics also apply to those people who suffer from allergic rhinitis.

Whether your condition is seasonal or perennial, there are many drugs that ease the symptoms of allergic rhinitis. A large number of them are available without a prescription. The most commonly used drugs are antihistamines, which are generally effective for both preventing and stopping attacks. To be fully effective, antihistamines must be taken regularly, often for several days at a time. Some common side effects from antihistamines are drowsiness, and dryness in the nose and throat. These may be more trouble some than the allergic rhinitis itself. Since antihistamines often make you sleepy, you should never take them if you intend to drive a motor vehicle or to operate machinery within the next few hours.

For quick relief from a stuffy nose, you can use decongestant nose drops or nasal sprays,

which can ease symptoms within minutes. Do not use such medicines often or regularly, however. They eventually aggravate the very symptoms they are supposed to suppress.

Professional help: There are quite a few symptom suppressing drugs that are available only with a prescription. If you do not get relief from any of the self -help measures suggested above, your physician may prescribe a type of antihistamine that works better for you than the non-prescription types. Another possible treatment for you is the use of a steroid spray.

All of these drug treatments merely suppress symptoms. They do not alter the basic allergic reaction. The only possible cure for allergic rhinitis is a series of injections designed to desensitize your system to the allergen or allergens that bother you. This is possible only if you have a skin test and successfully identify the substance or substances that bother you. In the treatment, your physician gives you a series of injections containing increasingly strong concentrations of your particular allergen in an attempt to stop your reactions.

This treatment is not always successful, and it takes a long time to complete the series of injections. Before you decide to have desensitization treatment, you should consider the possibility that it may not work for you and discuss the risks and benefits with your physician.