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.
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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
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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
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