Allergy symptoms appear when the immune system reacts to an allergic substance that has entered the body as though it was an unwelcomed invader. The immune system will produce special antibodies capable of recognizing the same allergic substance if it enters the body at a later time.
When an allergen reenters the body, the immune system rapidly recognizes it causing a series of reactions. These reactions often involve tissue destruction, blood vessel dilation, and production of many inflammatory substances including histamine. Histamine produces common allergy symptoms such as itchy, watery eyes, nasal and sinus congestion, headaches, sneezing, scratchy throat, hives, shortness of breath, etc. Other less common symptoms are balance disturbances, skin irritations such as eczema, and even respiratory problems like asthma.
Many common substances can be allergens. Pollens, food, mold, dust, feathers, animal dander, chemicals, drugs such as penicillin, and environmental pollutants commonly cause many to suffer allergic reactions.
One of the most significant causes of allergic rhinitis in the United States is ragweed. It begins pollinating in late August and continues until the first frost. Late springtime pollens come from the grasses, i.e., timothy, orchard, red top, sweet vernal, Bermuda, Johnson, and some bluegrasses. Early springtime hay fever is most often caused by pollens of trees such as elm, maple, birch, poplar, beech, ash, oak, walnut, sycamore, cypress, hickory, pecan, cottonwood, and alder. Colorful or fragrant flowering plants rarely cause allergy symptoms because their pollens are too heavy to be airborne.
Certain allergens are present all year long. These include house dust, pet danders, some foods and chemicals. Symptoms from these are frequently worse in the winter when the house is closed up and where there is poor ventilation.
Mold spores can also cause allergy problems. Molds are present all year long, and grow outdoors and indoors. Dead leaves and farm areas are common sources for outdoor molds. Indoor plants, old books, bathrooms, and damp areas are common sources of indoor mold growth. Mold is also common in foods, such as cheese and fermented beverages.
Allergies are rarely life threatening, but often cause lost work days, decreased work efficiency, poor school performance, and a negative effect on the quality of life. Considering the millions spent on antiallergy medications and the cost of lost work time, allergies cannot be considered a minor problem.
For some allergy sufferers symptoms may be seasonal, but for others it is a year-round discomfort. Allergy symptom control is most successful when multiple management approaches are used simultaneously. They may include minimizing exposure to allergens, desensitization with allergy shots, and medications.
If used properly, medications, including antihistamines, nasal decongestant sprays, steroid sprays, saline sprays, and cortisone-type preparations, can be helpful. Even over-the-counter drugs can be beneficial, but some may cause drowsiness.
The most appropriate person to evaluate allergy problems is an otolaryngologist (ear, nose, and throat specialist). Aside from gathering a detailed history and completing a thorough examination of the ears, nose, throat, head, and neck, the doctor will offer advice on proper environmental control and evaluate the sinuses to determine if infection or structural abnormality (deviated septum, polyps) is contributing to the symptoms.
In addition, the doctor may advise testing to determine the specific allergen that is causing discomfort. In some cases immunotherapy or allergy shots may be recommended. Immunotherapy is a unique treatment because it induces the build up of protective antibodies to specific allergens.
Drugs for stuffy nose, sinus trouble, congestion, and the common cold constitute the largest segment of the over-the-counter market for America's pharmaceutical industry. When used wisely, they provide welcome relief for at least some of the discomforts that affect almost everyone at one time or another and that affect many people chronically. Drugs in these categories are useful for relief of symptoms from allergies, upper respiratory infections i.e., sinusitus, colds, flu), and vasomotor rhinitis (a chronic stuffy nose caused by such unrelated conditions as emotional stress, thyroid disease, pregnancy, and others). These drugs do not cure the allergies, infections, etc.; they only relieve the symptoms, thereby making the patient more comfortable.
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. The first few doses cause the most sleepiness; subsequent doses are usually less troublesome.
Typical antihistamines include Benadryl,®* Chlor-Trimetron,®* Claritin,® Dimetane,®* Hismanal,® Nolahist,®* PBZ,®* Polaramine,® Seldane,® Tavist,®* Teldrin,® Zyrtec,® etc.
Congestion in the nose, sinuses, and chest is due to swollen, expanded, or dilated blood vessels in the membranes of the nose and air passages. These membranes have an abundant supply of blood vessels with a great capacity for expansion (swelling and congestion). Histamine stimulates these blood vessels to expand as described previously.
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®*), phenylpropanolamine (Dura-Vent,® Exgest,® Entex,® Propagest®), and pseudoephedrine (Novafed,®* Sudafed®* etc.)
* May be available over-the-counter without a prescription. Read labels carefully, and use only as directed.
Theoretically, if the side effects could be properly balanced, the sleepiness caused by antihistamines could be cancelled by the stimulation of decongestants. Numerous combinations of antihistamines with decongestants are available: Actifed,®* A.R.M.,®* Chlor-Trimeton D,®* Claritin D,® Contac,®* CoPyronil 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.
Decongestants and/or antihistamines are the principal ingredients in "cold" remedies, but drying agents, aspirin (or aspirin substitutes) and cough suppressants may also be added. The patient should choose the remedy with ingredients best suited to combat his own symptoms. If the label does not clearly state the ingredients and their functions, the consumer should ask the pharmacist to explain them.
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 have used the sprays for months and years continuously) 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.
(The above description and advice does not apply to the type of prescription anti-allergy nose sprays that me be ordered by your physician.)
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