Spring and fall are peak allergy seasons in many areas, with spring trees still pumping out millions of grains of pollen each day and the summer grasses already starting to contribute their share. Sneezing, running nose, and itching – itchy eyes, itchy nose, itchy throat – wouldn't it be great to be able to prevent allergies before they even got started.

Preventing asthma and allergies is possible, according to a study in the June 2003 issue of Thorax. Children at high risk for asthma and allergies were recruited in 1990 to be part of this study. Half of them went about life as normal, and the other half had a low-allergy diet as infants – starting with breast milk (with moms on a low-allergy diet) or Nutramigen formula (no milk or soy-based formula). This group of families also undertook significant measures to avoid exposure to house dust during infancy.

Avoiding inhaled allergens, though, may be another story. Other studies have shown that babies who are exposed to dogs and cats before the first birthday, for example, are far less likely to develop allergies later. It seems to me that the nose is designed to detect changes (which is why you often no longer notice even very strong odors if you are around them long enough). It seems to me that maybe a baby’s nose learns what is "normal" to have around them in the air during the first year or so, and then begins to consider some later arrivals as dangerous invaders – the body develops an allergic response to them.

Allergies happen when the body is tricked into thinking that harmless particles are dangerous invaders. The immune system tries to get rid of these allergens by sneezing them out, flushing them out with tears or mucus, or dislodging them with nose rubbing. It tries to prevent them from getting into the lungs by constricting the airways. These are all normal responses to toxins and viruses. They are allergies if the trigger is not really a problem.

There may have been other differences between the two groups in the study. One half certainly worked harder and paid more attention to allergy issues. We still have a lot to learn. What’s exciting about this breakthrough study is that it demonstrates that preventing allergies, asthma, and eczema is truly possible. Now we just have to learn how best to do it.

Antihistamines
Histamine is an important body chemical that is responsible for the congestion, sneezing, and runny nose that a patient suffers with an allergic attack or an infection. Antihistamine drugs block the action of histamine, therefore reducing the allergy symptoms. For the best result, antihistamines should be taken before allergic symptoms get well established.

The most annoying side effect that antihistamines produce is drowsiness. Though desirable at bedtime, it is a nuisance to many people who need to use antihistamines in the daytime. To some people, it is even hazardous. These drugs are not recommended for daytime use for people who may be driving an automobile or operating equipment that could be dangerous. Newer non-sedating antihistamines, available by prescription only, do not have this effect. The first few doses cause the most sleepiness; subsequent doses are usually less troublesome.

Typical antihistamines include Allegra®, Benadryl®, Chlor-Trimetron,®, Claritin®, Clarinex®, Teldrin®, Zyrtec,® etc.

Nose Sprays
The types of nose sprays that can be purchased without a prescription usually contain decongestants for direct application to nasal membranes. They can give prompt relief from congestion by constricting blood vessels. However, direct application creates a stronger stimulation than decongestants taken by mouth. It also impairs the circulation in the nose, which after a few hours, stimulates the vessels to expand to improve the blood flow again. This results in a "bounce-back" effect. The congestion recurs. If the patient uses the spray again, it starts the cycle again. Spray–decongestion– rebound–and more congestion.

In infants, this rebound rhinitis can develop in two days, whereas in adults, it often takes several more days to become established. An infant taken off the drops for 12 to 24 hours is cured, but well-established cases in adults often require more than a simple "cold turkey" withdrawal. They need decongestants by mouth, sometimes corticosteroids, and possibly (in patients who continuously have used the sprays for months and years) a surgical procedure to the inside of the nose. For this reason, the labels on these types of nose sprays contain the warning "Do not use this product for more than three days." Nose sprays should be reserved for emergency and short term use.

Decongestants, on the other hand, cause constriction or tightening of the blood vessels in those membranes, which then forces much of the blood out of the membranes so that they shrink, and the air passages open up again.

Decongestants are chemically related to adrenalin, the natural decongestant, which is also a type of stimulant. Therefore, the side effect of decongestants is a jittery or nervous feeling. They can cause difficulty in going to sleep, and they can elevate blood pressure and pulse rate. Decongestants should not be used by a patient who has an irregular heart rhythm (pulse), high blood pressure, heart disease, or glaucoma. Some patients taking decongestants experience difficulty with urination. Furthermore, decongestants are often used as ingredients in diet pills. To avoid excessively stimulating effects, patients taking diet pills should not take decongestants.

Typical decongestants are phenylephrine (Neo-Synephrine®*), and pseudoephedrine (Sudafed®, etc.)

* May be available over–the–counter without a prescription. Read labels carefully, and use only as directed.

Combination Remedies
Theoretically, if the side effects could be properly balanced, the sleepiness sometimes caused by antihistamines could be cancelled by the stimulation of decongestants. Numerous combinations of antihistamines with decongestants are available: Actifed,®* Allegra-D,® Chlor-Trimeton D,®* Claritin D,® Contac,®* Co-Pyronil 2,®* Deconamine,® Demazin,®* Dimetapp,®* Drixoral,®* Isoclor,®* Nolamine,® Novafed A,® Ornade,® Sudafed Plus,® Tavist D,®* Triaminic,®* and Trinalin,® to name just a few.

A patient may find one preparation quite helpful for several months or years but may need to switch to another one when the first loses its effectiveness. Since no one reacts exactly the same as another to the side effects of these drugs, a patient may wish to try his own ideas on adjusting the dosages. One might take the antihistamine only at night and take the decongestant alone in the daytime. Or take them together, increasing the dosage of antihistamine at night (while decreasing the decongestant dose) and then doing the opposite for daytime use.