Unsuspecting allergy victims have more to fear than just an allergen. They may also be victimized by those who would rush to treat their condition. Abuses include the overuse of allergy tests and shots, mail-order diagnosis, and the treatment of nonexistent food allergies. If you have allergies, as an estimated one out of five Americans do, learn the truth about the problem and what really helps before you fall for a questionable cure.
The Cause of Allergies: Immunity Gone Haywire
The tendency to become sensitized to allergens is largely inherited. Symptoms can range from merely annoying to life-threatening. Most sufferers have hay fever, or "allergic rhinitis." Less-common problems include asthma, skin diseases such as atopic eczema, and food allergies. Symptoms vary, but the underlying cause is the same—a glitch in the body's immune defenses. The immune system protects against disease-causing germs, such as bacteria and viruses. But allergic people have an immune system that also reacts to harmless material, such as pollen, as if it were a threat.
Initial encounters with an allergen may prompt your immune system to form antibodies, which deploy on specialized cells called mast cells. When coated with antibodies, mast cells are like mines bristling with detonators. Millions of them lie in the respiratory and digestive tracts and in the skin, waiting for the right allergen to come along. When one does, the mast cells explode, releasing powerful chemicals such as histamine. These chemicals engage the "invader" but can also inflame nearby tissues, cause hives to form and airways to narrow, and stimulate mucus production in the nose and sinuses.
Usually, this reaction causes symptoms of hay fever, such as watery or itchy eyes, sneezing fits, and a runny or stuffy nose. (Despite the name, sufferers do not react to hay and do not run a fever.) The main culprits are pollens: primarily from trees in spring, grasses in early summer, and ragweed in late summer and early fall.
Self-Treatment With OTC Remedies
Many allergic people have seasonal hay fever. Those who suffer from mild symptoms can try to ward off the allergy-producing substance (or substances) by installing an air conditioner or taking a well-timed vacation to a pollen-free area. If the first option isn't effective and the second one isn't feasible, some comfort may be found in a carefully selected over-the-counter (OTC) remedy or two, most likely an antihistamine and possibly a decongestant.
Antihistamines Antihistamines are the mainstay of hay fever treatment, indeed providing rapid temporary relief to most sufferers. They act by preventing histamine from exerting its noxious effects. Some antihistamines also have a drying effect on nasal secretions.
While OTC antihistamines rarely cause serious side effects in teenagers and adults, drowsiness is a common complaint. That makes their use undesirable when you need to be alert, and dangerous when you drive a car or operate machinery. Using antihistamines in combination with alcohol, tranquilizers, or other central nervous system depressants magnifies their sedative effect and can be hazardous.
Some people develop a tolerance to this side effect after using antihistamines for a while. If drowsiness is a problem, try taking the antihistamine only at bedtime at first and then increase the dosage by cautiously introducing daytime medication over the course of the first week.
Certain types of antihistamines are more likely than others to produce drowsiness in the first place. Of the three main chemical classes of antihistamines listed, the alkylamines generally have the least sedative effect and the ethanolamines the most. The ethylenediamines fall somewhere between. (Phenindamine tartrate, a compound with a different chemical structure from the others, commonly stimulates rather than sedates.)
While those chemical groupings may be useful as a general guide, the side effects of antihistamines can vary widely from one individual to the next. You might be knocked out by an alkylamine and function very well on an ethylenediamine; someone else might react just the opposite. You may need to experiment with different products in different chemical classes to find the most suitable one.
CU's medical consultants suggest confining experimentation to those OTC products containing one of the antihistamines at its recommended dosage level. At this time, Chlor-Trimeton, Dimetane, Novahistine, and Pfeiffer Allergy Tablets are among the brand-name products that meet those ingredient and dosage requirements. Before making a purchase, ask a pharmacist whether any of the antihistamines is available as a generic product that can save you money.
Once a satisfactory antihistamine has been found, you may discover that the product no longer works after a while. Just as it is possible to develop a tolerance to the drug's sedative quality, it is also possible to become tolerant to its therapeutic effect. If that happens, switch to another antihistamine.
Curiously, children sometimes react to antihistamine use with insomnia and stimulation of the central nervous system rather than with drowsiness. Because of antihistamines' less-predictable effects on children, anyone aged 6 to 12 should be given these drugs with caution. They should not be given to children under six except with the advice and supervision of a physician. Pregnant and lactating women, men with urinary problems, and people with asthma, glaucoma, or convulsive disorders should consult a physician before using antihistamines.
Decongestants An antihistamine is most effective if used before allergy symptoms become severe. But even then, it usually doesn't work well against a stuffy nose. So a hay fever sufferer may also need a decongestant, which can be taken either orally in pill or liquid form, or topically as nasal sprays or drops. The topical decongestants should be used cautiously—if at all—for hay fever, because treatment may be needed for many weeks and frequent use leads to dependency and "rebound congestion." People with high blood pressure, heart disease, diabetes, thyroid disease, or urinary problems should consult a physician before using any decongestant.
Because hay fever sufferers often use both decongestants and antihistamines, the two drugs are sold in combination in many OTC allergy products. Among combination products, Chlor-Trimeton Decongestant, Dimetapp, Fedahist, Ryna, Sudafed Plus, and Triaminic currently offer effective dosages of one recommended decongestant and one recommended antihistamine. Again, less-expensive generic versions may be available.
While taking a fixed-combination product may be more convenient than separate medications, it locks you into dosages that may not be exactly right. For example, if you are adequately medicated with less antihistamine, you might want to reduce the dose to alleviate drowsiness. But cutting down on the antihistamine dose would mean also reducing the decongestant dose—and perhaps rendering it totally ineffective. And since a stuffy nose might not always accompany the other symptoms, you would be medicating a nonexistent symptom if you took a combination product whenever hay fever flared up. Because of such drawbacks, CU's medical consultants suggest using each medication separately—at least until you have confirmed the individual ingredients and dosages that are right for you.
Shotgun Remedies Most OTC cold and allergy products include far more than two ingredients. These "shotgun remedies" may boast five or more, possibly including caffeine, one or more painkillers, an anticholinergic (a drying agent) such as atropine sulfate or belladonna alkaloids, among others. Of these additions, only a painkiller might make sense—but even then, not every time. Some hay fever victims do sometimes suffer headaches, but this is rarely an ongoing symptom. As with antihistamine and decongestant, you'd be much better off taking the pain-reliever component separately, and only as needed.
CU's medical consultants believe the heavily advertised "timed-release" or "sustained-action" cold and hay fever products (including Contac and Dristan capsules) should be avoided not only because of what's in them, but because of the unpredictable rate at which they work in any given individual. If the ingredients are released too slowly, there may be no therapeutic effect. If they are released too quickly, side effects may increase in number and severity.
Even if a satisfactory OTC product for your allergy is found, be on the alert for complications. Pain or popping sounds in the ear may indicate a problem that could cause vertigo (an unbalanced spinning sensation often accompanied by nausea) and eventually lead to hearing loss. Pain above the teeth, in the cheeks, above the eyes, or on the side of the nose could indicate a bacterial sinus infection. Persistent coughing, difficulty in breathing, and wheezing may signal asthma, a more serious allergic ailment than hay fever. If any of these symptoms occurs, see a physician.
Seeking Professional Treatment
Some people need more than an OTC remedy. They may suffer debilitating hay fever symptoms for months on end or even year-round. Or they may have asthma aggravated by allergies, or even life-threatening reactions to certain insect stings. They require professional help.
Whatever the problem, the critical first step is a thorough medical history. The series of questions—what are your symptoms, when and where do they occur, and so on—may reveal that your problems actually arise from something other than an allergy. Often symptoms may stem from a respiratory infection, tobacco smoke, or some other nonallergic cause. If you do have allergies, the history can narrow the possibilities. Seasonal symptoms, for example, suggest that one or more pollens are at fault. Recurring symptoms may point to some factor at home or work, such as mold, dust, or pets.
A diagnostic test may also be needed to pin down the allergy. Most commonly used is a skin test, which detects antibodies your body has developed against specific allergens. Typically, using the "scratch test" method, the doctor or assistant uses a penlike instrument to make a series of pricks on your back or forearm. A drop of allergen extract is then placed on each puncture. Many different allergens can be tested in this manner. Alternatively, some specialists prefer to inject the extract directly into the skin (intradermal skin test). A positive test produces a small, circular welt around the puncture or injection site within 10 to 20 minutes. The bigger the welt, the greater the sensitivity to the allergen.
Once an allergy has been identified, the most effective way to treat it is to avoid what causes it. With pollen, of course, that's usually not possible—although an air conditioner may help keep it out of the house. For many other allergens, an allergist will recommend avoidance before trying any other treatment. If your cat makes you wheeze, no treatment can rival giving it away. If you react to house dust, removing bedroom rugs and putting mattresses and pillows in zippered, airtight covers may ease the problem. A dehumidifier can help rid your basement of mold.
When avoidance isn't possible, the next-best solution is to relieve symptoms. If OTC antihistamines and decongestants aren't helpful, an allergist may prescribe other drugs. During the last 10 years, new prescription drugs with reduced side effects have enhanced allergy treatment significantly. Here's a brief rundown of the most important ones:
Terfenadine (Seldane), Introduced in 1985, this is the first of a new breed of antihistamines that seldom cause drowsiness. Its disadvantage is that it costs much more than OTC antihistamines at present. Competition may lower its price tag. By 1990, the FDA is expected to approve two other nonsedating antihistamines: astemizole (Hismanal) and loratadine (Claritin). Both are longer-acting than terfenadine—which may soon become available over-the-counter.
Cromolyn Sodium (Nasalcrom) This liquid nasal spray is quite effective in preventing symptoms of both asthma and hay fever. (It should not be used to treat an acute asthma attack; it could make matters worse.) Cromolyn appears to toughen mast cells, making them less likely to break apart and release histamine when confronted with an appropriate allergen. It is notable for its lack of side effects.
Steroid Nasal Sprays Containing either beclomethasone dipropionate (Vancenase, Beconase) or flunisolide (Nasalide), these are especially effective against nasal congestion. While their action is not immediate, it is limited to their target area—the nose and bronchial passages—which minimizes the risk of side effects that can occur with other dosage forms of steroids.
Optimal treatment may require a combination of drugs—for instance, an antihistamine to help watery, itchy eyes and a steroid spray for nasal congestion. Such therapy can usually relieve symptoms in all but the most severe cases.
The Shot Doctors
Although they have their place in allergy therapy, injections are perhaps the most overused and misused treatment. In recent years, their popularity has been boosted by the proliferation of mail-order allergy laboratories around the country. These labs will analyze a blood sample to identify the patient's supposed allergies and send a printout of the results back to the doctor, who can then order extracts to use in allergy shots.
A blood test is more expensive and less sensitive than a skin test, which should be performed only by a trained allergist. The main advantage of a blood test is that it requires just a single puncture, making it more acceptable for toddlers and for people with extensive skin disease.
However, mail-order diagnosis is tempting to some doctors with little or no training in allergy. It offers a simple way to treat allergic patients by administering shots instead of recommending drugs or referring them to specialists. (After all, patients treated with shots return to the doctor's office much more frequently than those on prescription drugs.)
But mail-order diagnoses may be inaccurate or misleading. An erroneous diagnosis can lead to costly and potentially hazardous treatment—a series of shots that will set you back several hundred dollars a year for two or more years. And even with an accurate diagnosis, allergy shots are rarely appropriate treatment. They're unnecessary for most hay fever victims, and they don't work at all against food allergies.
Too many patients are put on shots simply because they have positive skin or blood tests. Often these people don't even have a history of allergy to the putative antigen. What's more, overzealous skin-testing can increase the chances of a false positive result. Indeed, some doctors give an excessive number of skin tests, sometimes performing 100 or more in a single visit—a practice that coincidentally escalates their fees. The American Medical Association's Council on Scientific Affairs recently stated that the number of skin tests "should rarely exceed 50."
Even significant allergies may not warrant shots. For example, a skin test may suggest you're extremely sensitive to Bermuda grass. But that's a problem only if you live in or visit an area where Bermuda grass is prevalent. If you don't, you surely don't need shots.
The Time for Shots
When an allergy has been accurately diagnosed, treatment with drugs has fallen short, and avoidance of the allergen is impractical, the patient may indeed be a candidate for allergy shots. The shots can be effective against some allergens you inhale—such as pollens that cause hay fever or aggravate asthma—and against allergies to insect stings.
Treatment begins with shots once or twice a week. The first injection contains a very dilute antigen dose, so as not to provoke an allergic reaction, such as generalized itching or hives. Each succeeding shot contains a higher concentration of the allergen. The aim is to increase the concentration gradually to a maintenance dose—the highest concentration that the patient can tolerate without an allergic reaction. That process commonly takes from four to six months. After that, the patient receives monthly injections of the maintenance dose, generally for at least two years.
One of the major abuses involving allergy shots—even when shots are likely to be appropriate—is treatment that lasts too long. You should expect to see improvement after one year, or two years at most. Shots that don't produce an improvement within two years should be discontinued. When shots do work, they should be kept up for three to five years, after which they usually can be stopped. For about half the patients, relief from symptoms will persist indefinitely. If symptoms recur, another course of shots can always be undertaken.
Allergy shots can work well when used appropriately. But even in the right situation, shots have drawbacks that should make them the treatment of last resort. First of all, they contain allergens, so there's always the risk of an allergic reaction. A patient receiving shots walks a fine line: Improvements are greatest at the highest maintenance dose, but that's also the dose most likely to cause allergic reactions. In very rare cases, such reactions can be fatal.
Second, allergy shots pose a danger because of the uncertain quality of their extracts. In contrast to other types of drugs, most allergenic extracts lack uniform standards of potency, and in some instances the differences can be significant. The dust extract sold by one company, for instance, may be as much as 1000 times stronger than a similar extract sold by another. That could be dangerous, especially if the doctor were to switch from a weaker to a stronger extract in the course of treatment.
So far, only about a dozen of the 1500 different extracts on the market have been standardized. They include some of the most important ones, however, such as short ragweed, several grasses, cat, and house-dust mites (the major allergen in house dust).
Which Extracts Work?
In 1974, the FDA convened a panel of allergy experts to review the efficacy of extracts. In 1985, the panel concluded that many of the 1500 marketed extracts were effective for diagnostic use in skin tests. Their value in treatment, however, was far less certain. The panel found convincing proof of efficacy for only a handful of extracts, including ragweed, certain grasses, mountain cedar, and dust mites. They reasoned that extracts of other inhaled allergens would probably work also.
Here's the current status of some commonly used extracts:
Ragweed Most immunotherapy research has looked at ragweed, the major cause of hay fever. Well-controlled studies show that shots for ragweed pollen work for about 85 percent of patients.
Pollens While clinical studies are lacking for many pollens, such as birch, oak, red maple, annual bluegrass, and others, most authorities believe that pollen extracts are effective.
House Dust While some allergists say these extracts work, others strongly disagree. The raw materials for several such extracts come from the contents of vacuum-cleaner bags, with no consistency from one batch to another. Analyses show that the extracts contain anything from dog and cat dander to allergens associated with dust mites, rodent hairs, molds, and other substances. The FDA advisory panel concluded that house-dust extracts are potentially unsafe and should be taken off the market, but the FDA has not yet acted on the panel's recommendation.
Mold A few studies that evaluated mold extracts produced inconclusive results. CU's allergy consultants said they prefer to treat mold allergies with drugs whenever possible.
Cats An estimated 58 million cats live in 27 million American homes, and many people are allergic to them. Until recently, researchers thought the problem was mainly cat dander. Now they know that most people allergic to cats are also sensitive to the saliva cats apply to themselves when grooming. Three clinical studies have shown that while shots allow people to tolerate cats for longer periods before symptoms hit, many of these people remain quite sensitive. While cat-extract shots may help people who are exposed to cats occasionally, perhaps when visiting cat owners, such shots are totally ineffective for allergic people who live with cats. For those people, the most effective measure is to find another home for the cat—or at least keep it out of the bedroom.
Insects For people who experience serious reactions from insect stings, studies show that allergy shots afford almost complete protection against harmful effects from subsequent stings.
Asthma and Allergies
Should asthmatics get allergy shots? Some doctors think so, but such treatment remains controversial. Many of America's 15 million asthmatics do have allergies—about half the adults and 90 percent of children. Many people with adult-onset asthma, which can be quite debilitating, have no allergies at all. When allergies do provoke asthma, avoidance is still the best treatment. Pets and dust often cause problems; removing them may provide relief.
Today's drugs, the second line of defense, usually control the wheezing, coughing, and shortness of breath that occur with asthma. Bronchodilators, for example, make breathing easier by widening bronchial tubes that have been narrowed by muscle spasm, inflammation, and mucus. Asthmatics with minimal wheezing may often obtain short-term relief with OTC bronchodilator inhalers containing epinephrine and similar drugs. Longer-acting bronchodilator sprays that require a prescription include those containing albuterol or terbutaline. Theophylline, another long-acting bronchodilator, can be taken orally. Oral forms of albuterol and terbutaline are also available.
Some asthmatics—those not helped by avoidance or drugs and whose attacks are serious enough to require hospitalization—might be candidates for allergy shots. But their allergies must first be documented. Asthma can be triggered by many factors besides allergies, including exercise, stress, respiratory infections, cold weather, and cigarette smoke. Current evidence suggests that shots may be worth a try in carefully chosen asthma patients, particularly those with allergies to grasses and cats.
Food Allergies and Intolerances
Pop-medicine publications have spread the word that food allergies are a major public-health problem, causing myriad physical and psychological symptoms. Actually, true food allergies, in which a food provokes an immune response, are uncommon. Only about 5 percent of children and less than 2 percent of adults have well-documented food allergies.
What people call food allergies are often food intolerances. Some of those are individual idiosyncrasies without a detectable physical basis. Millions of Americans report such idiosyncrasies and get along simply by avoiding the offending food. But some food intolerances arise from well-identified causes. Many people have trouble with milk, for example, because they're deficient in an enzyme needed to digest lactose (milk sugar). They may experience bloating, diarrhea, or other gastrointestinal symptoms from milk, ice cream, and other dairy products.
The distinction between food intolerance and food allergy is important. People with a true food allergy must avoid the offending food in any quantity and at all times. But those with a mild food intolerance may be able to eat small to moderate amounts of a problem food with little discomfort. Mistaking a food intolerance for a food allergy can needlessly restrict what you eat and even result in nutritional deficiencies.
The main culprits in true food allergies are cow's milk protein, egg whites, various kinds of nuts, and, especially, seafood. If you're allergic to any of them, you might experience one or more of several symptoms: nausea, vomiting, diarrhea, rashes, itching, difficulty breathing. In rare cases, even fatal reactions can occur. (Patients with proven food allergies are commonly advised to carry a preloaded epinephrine syringe to take in case of a severe reaction.) There's no scientific evidence, however, that food allergies cause psychological or behavioral problems.
If you think you have a food allergy, you should be referred to a physician who is board-certified as an allergist (one who has passed the examination administered by the American Board of Allergy and Immunology). You may receive skin tests using food extracts. A positive test result requires confirmation, through either a well-documented history of allergic reactions to the food or a controlled oral "challenge," in which the suspect food is served under the supervision of a physician. If you do have a food allergy, the allergist will tell you there is only one effective treatment: Avoid the food. Shots, a qualified allergist will tell you, are totally useless as a therapy for food allergies.
But there are other physicians who contend that food allergies can be treated, often with extracts that you administer to yourself. Among those physicians are some otolaryngologists—ear, nose, and throat specialists. In recent years, about 20 percent of such specialists have turned to allergy treatment, calling themselves "otolaryngic allergists." Such self-styled allergists contend there's no limit to the insidious things a food can do to you. "The list of possible disorders that can be caused by food allergies is almost endless," declares a pamphlet published by the American Academy of Otolaryngic Allergy. "Even more startling," continues the pamphlet, "is the mounting evidence that foods and chemicals may cause severe difficulties in the nervous system and in the mind itself." But fortunately, it reassures, "most cases of food allergy can be helped" through the use of "modern procedures."
A second group of unorthodox allergy practitioners includes physicians of various types who call themselves clinical ecologists. They contend that not only foods but the chemicals around us trigger numerous physical and psychological problems. Otolaryngic allergists and clinical ecologists often use similar techniques for diagnosing and treating food allergies. One is the "intracutaneous provocative food test," in which the food extract is injected into the arm supposedly to provoke—and thereby detect—food allergy. Once a reaction has been provoked, a weaker solution of the extract is then injected to "neutralize" it. That neutralizing dose is then used for food-allergy treatment whenever the patient expects to confront the food and simply must eat some. A variation on this testing-and-treatment theme is the "sublingual" method, in which food extract drops are placed under the tongue instead of injected.
Several controlled studies have now evaluated those techniques for efficacy. All concluded that the measures are ineffective both for diagnosing and for treating food allergies. In 1983, the Health Care Financing Administration (HCFA) proposed to exclude both intracutaneous and sublingual methods from coverage under Medicare. The HCFA said both of the methods lacked "scientific evidence of effectiveness." The HCFA proposal prompted the otolaryngic allergists to begin a clinical study of those methods, which they'd been using uncritically since 1961. CU was allowed to look at the study before it was published. We asked two board-certified allergists familiar with allergy research to review it. They independently identified serious flaws in the study's research methods.
The California Medical Association, the American Academy of Allergy and Immunology, and a committee of the Ontario Ministry of Health have also assessed provocation testing and neutralization therapy. They all judged the techniques to be unproven. The American Academy of Allergy and Immunology described the techniques as having "no plausible rationale or immunologic basis."
In 1983, an FDA advisory panel on allergenic extracts concluded that food extracts are unsafe and ineffective for treating food allergy. Physicians can still use the extracts any way they want, because the FDA can't dictate medical practice. But unapproved use of a drug increases a physician's vulnerability in the event of a malpractice suit and may not be covered by insurance plans.
If you have reason to suspect hay fever and your symptoms are mild, you might experiment with OTC remedies, following the guidelines outlined earlier. An antihistamine and/or a decongestant may be all that you need to relieve seasonal symptoms. Then again, there may be no OTC remedy that gives sufficient relief. Or there may be side effects as distressing as the original symptoms. If you're not satisfied with the choice of nonprescription medications—or not sure you have hay fever—consult your physician. He or she may be able to help you identify and avoid your allergen, offer prescription drugs, or refer you to an allergist to evaluate your condition and possibly consider shot therapy.
But before resorting to shots for any allergy, a physician should first determine that:
Allergists do make exceptions and may choose to administer allergy shots without following such stringent guidelines. A singer, for instance, may need shots to be entirely free of symptoms. An airline pilot may want shots in order to avoid any sedating effects from drugs.
For most patients, though, drugs are preferable. They cost less; at an average of $20 per shot, a typical series of shots plus a consultation will come to about $400 a year. They are usually needed for only a few weeks or months each year. And they work faster; you can see results in a day or two versus a year or more for shots. Even when successful, shots may fail to provide complete relief; patients often need drug therapy as well.
If you're seeking help for allergies that can't be handled by OTC medications, check with your physician. He or she may recommend a visit to a board-certified allergist, who has received specialized training in treating such problems. You can ask your physician about the allergist's qualifications or you can call the American Board of Allergy and Immunology in Philadelphia (215-349-9466) for the information. In addition, the "Directory of Medical Specialists," which is available in the reference section of many public libraries, includes a listing of board-certified allergists.