Managing Allergies in Active People

Malcolm N. Blumenthal, MD, with Carl Sherman

THE PHYSICIAN AND SPORTSMEDICINE - VOL 25 - NO. 8 - AUGUST 97

In Brief: Though exercise does not appear to cause allergies, active patients require special attention when allergies appear. Physical activity may increase contact with substances that cause hay fever, trigger asthma episodes, or result in contact dermatitis. Nonspecific irritants (like chlorine or air pollutants) and allergens often interact in the context of exercise, and strenuous activity may produce allergic-like symptoms that complicate the clinical picture. An athletic patient's exercise patterns and preferences should be kept in mind in evaluating allergies, devising treatment strategies, and choosing medication.

Untreated or poorly controlled allergies don't mix well with exercise. Your athletic patients may suffer as much as anyone from the sneezing of hay fever or the itching of contact dermatitis, with the additional frustration of having symptoms—or their treatment—interfere with their ability to work out or compete.

Evaluating allergies in this population raises special issues about exposure and nonallergenic, exercise-related irritants that may confuse diagnosis and possibly aggravate or precipitate symptoms. Treatment should aim at taming the allergy in a way that makes it possible for the patient to enjoy the benefits of his or her favored athletic pursuits.

Can exercise cause or worsen allergies?
Exercise by itself probably does not cause allergies. Allergies such as hay fever (allergic rhinitis), contact dermatitis, and asthma are mediated by the immune system, and it is true that exercise may affect immune function. Evidence suggests that moderate exercise increases immune efficiency (some studies show fewer respiratory infections in runners, for example) (1), and that excessive training has an opposite effect, as indicated by the observation that upper respiratory infections are more frequent in runners who train most heavily, possibly reflecting immune impairment (2).

However, no studies give much reason to believe that exercise promotes the specific, adverse immune reactions responsible for allergy, or that allergic conditions are more common among athletes than sedentary people.

Anecdotal reports suggest an increased incidence of asthma among Olympians and other highly trained athletes (3,4). But allergy is only one of many factors that trigger or exacerbate asthma, and the increase may well be due to an effect of exercise itself (exercise-induced asthma).

It appears that exercise alone or in association with an allergic reaction may trigger anaphylaxis, a clinical picture featuring hives, swelling, and possibly a drop in blood pressure. For example, there is some evidence that eating a certain food a person is allergic to, such as celery, in association with exercise will cause anaphylaxis, while either variable by itself will not.

Of course, exercise can increase an individual's exposure to allergens and general irritants such as pollen, cold air, noxious agents, pollution, and smoke.

This is obviously true, for example, for patients who have inhalant allergies. Hay fever is likely to be exacerbated when an individual who is allergic to ragweed or grass exercises outdoors when pollen concentrations are high. Someone who is allergic to mold may develop symptoms if he or she hikes, hunts, or fishes in woody areas where dead leaves promote the growth of mold, or spends time in damp locker rooms.

By the same token, a person who is allergic to algae may suffer urticaria, hay fever, or asthmatic symptoms after swimming in a lake or river. And direct contact with poison ivy or oak can cause contact dermatitis. Allergies to proteins in mayflies or caddis flies are not uncommon, and athletic pursuits may bring an individual to places where these insects are abundant. Exposure to other insect allergens can occur on the athletic field or training area when players come in contact with the insect's habitat (eg, yellow jacket nests, fire ant mounds).

How can exercise complicate or confuse the allergy picture?
Exercise may induce symptoms that resemble those of allergy. More than 80% of asthmatics, for example, suffer exercise-induced asthma during or after strenuous activity (5). Urticaria and angioedema may be triggered by exposure to cold or heat during activity, or by exercise itself.

In addition to complicating the diagnosis, these reactions may interact with and exacerbate allergic manifestations, or vice versa. Exposure to cold in a susceptible person can worsen the nasal symptoms of hay fever; some asthmatics are troubled by exercise-induced asthma only during the pollen season.

In the course of exercise, nonspecific irritants and allergic reactions can interact and exacerbate one another. People who have asthma may be far more sensitive to the effects of air pollution, for example, when their airways have already been primed by exposure to pollen, and suffer particularly severe symptoms if they run or work out when both pollen and pollutant concentrations are high. The same is true for people who have allergic rhinitis. Similarly, pollutants emitted by ice grooming machines in indoor ice arenas may compound respiratory distress in individuals whose airways or nasal passages are already inflamed by allergy.

While it is not a true allergen, the chlorine in a swimming pool may cause allergic-like reactions, such as eye irritation or respiratory symptoms (6), or exacerbate hay fever or other allergies.

What effect can allergy have on the capacity to exercise or engage in sports?
Allergic symptoms rarely preclude athletic participation, but they may have a greater or lesser impact on performance. Asthma may substantially reduce respiratory efficiency; the nasal congestion of hay fever can create a more subtle airway obstruction and alter breathing mechanics. These changes may not affect most people engaging in most exercise, but become noticeable under circumstances of high demand. For a highly trained athlete, subtle decrements in air exchange and increases in the work of breathing may make a perceptible difference in performance. In addition, hay fever and asthma are often accompanied by vague symptoms such as fatigue and headache, and these can take a toll on endurance, concentration, and motivation.

General discomfort, such as the itching caused by contact dermatitis, can conceivably create enough of a distraction to influence the outcome of competition.

How do you diagnose and evaluate allergy in active people?
Clinical history and examination will help distinguish allergy from other causes of similar symptoms. Wheezing and shortness of breath during exercise may be related to obesity, poor aerobic condition, hyperventilation due to psychological factors, or asthma. The cause of urticaria may be insect bites or stings. Some patients may have an allergic reaction such as anaphylaxis or hives from a honeybee sting or other hymenoptera, while other bites or stings such as mosquito bites do not cause such a reaction. Spider bites may cause large local reactions, but not an allergic reaction. Portuguese man-of-war stings may cause hives, but in most cases this is a toxic reaction.

A blood histamine or tryptase test is often helpful in confusing cases. High levels of histamine or tryptase indicate that the reaction in question is mediated by mast cell degranulation, which is characteristic of an immediate hypersensitivity or allergic reaction.

If allergy seems to be involved, the next order of business is to identify the specific triggers through a detailed exposure history. The time of year when symptoms appear or worsen and the circumstances in which they occur may suggest pollens, molds, or other allergens.

In most areas, tree pollens are the predominant airborne allergens in March through May, grasses in May through July, and ragweed in August and September. Outdoors, mold may be a factor whenever the ground is not covered with snow.

Certain fruits cross-react with pollens, and a history of food-related symptoms can provide useful clues. A person who is allergic to birch pollen may also have symptoms when he or she eats apples or bananas, and someone with ragweed allergy may react to melons.

Exposure to new environmental situations, such as to animals (eg, dog or cat) or to a dusty, carpeted room with high levels of mites, cockroaches, or mold, may influence respiratory allergy symptoms. Staying in a room where there was previous smoking or the use of irritants such as disinfectants may also influence the clinical picture.

Tests should be used to confirm suspicions aroused by history, but only when findings will be useful clinically (when it is possible to avoid exposure, for example). Skin testing with putative allergens is usually adequate (and less expensive than blood tests like radioimmunosorbent assay), but should be avoided when the risk of anaphylaxis is a concern.

How do you diagnose contact dermatitis?
The typical rash is itchy and red, with small papular vesicles that ooze and crust. The cause is a cellular-type, delayed hypersensitivity reaction.

While the symptoms of an IgE-mediated allergy like hay fever, hives, angioedema, or anaphylaxis appear quickly after exposure, contact dermatitis may take 2 to 5 days to occur. This can complicate identification of the offending substance; a careful history is necessary, and the location of the rash can be important. Lesions on the feet or arms point to vegetation such as poison ivy or oak. A rash about the waist may suggest allergy to elastic. Rubber or dyes in athletic shoes may cause a rash on the feet. A component of athletic tape, paratertiary-butylphenol formaldehyde resin, may cause a rash in patients who are sensitive to this compound (7).

The carrier components of analgesic and antibiotic salves and ointments used to treat athletic injuries may produce contact dermatitis.

Patch tests are useful in confirming sensitivity to a variety of allergens.

How do you manage allergies in athletes?
As with allergies in general, the first priority is reducing exposure to the extent possible. I often counsel patients to choose athletic activities with an eye toward avoiding offending allergens.

This may not be feasible when a favorite sport is involved. A passionate golfer is unlikely to let a grass allergy keep him or her off the course, and a dedicated runner will probably resist the idea of laying off for the duration of the ragweed season. Nor would it be advisable, except in extreme cases, to sacrifice the benefits of exercise to ameliorate symptoms that can be treated in other ways.

The primary goal of management should be allowing the patient to do what he or she wants to do. But when a patient is flexible and enjoys a number of different sports, knowledge of exposure risks can help guide him to adapt his activities to the time of year or make other modifications: to substitute tennis (on a hard court) for golf at critical times of year, or to run on an indoor track when pollen concentrations are particularly burdensome.

If patients cannot avoid the triggering agents, pretreatment with medication may prevent symptoms. Antihistamines, decongestants, or inhaled anti-inflammatories may be used before exposure in patients who have hay fever symptoms. Those who have asthma may wish to use an inhaled beta2 agonist before exposure or after onset of symptoms. It should be stressed that these medications can influence performance by causing drowsiness and may decrease cognitive skills. It is important that patients discuss their medication regimen with their physician.

How can planning help?
Concentrations of many pollens, such as ragweed, are typically highest in the morning, dropping at midday and rising to a small peak in the early afternoon. Patients who have respiratory allergies should be advised to schedule outdoor workouts with such fluctuations in mind. Individual pollens and reactions differ; I often suggest that patients keep a journal to track the times of day that work best for them.

By the same token, an attentive runner or cyclist may discover that some routes provoke less severe allergic reactions than others. For example, during the allergy season, many people can minimize respiratory distress by avoiding running or cycling on routes where air pollution levels are high, such as along busy highways.

When medications are necessary, which do you prefer?
Because allergic rhinitis and asthma are essentially inflammatory disorders, inhaled or intranasal anti-inflammatories are the logical first-line prophylactic agents of choice for some physicians, though others prefer antihistamines or beta agonists.

In my experience, corticosteroids (beclomethasone dipropionate, flunisolide, triamcinolone acetonide) are the most effective anti-inflammatory agents for hay fever and asthma. Systemic absorption appears to be slight, and they cause few side effects other than local irritation and increased incidence of fungal infection. (Concerns remain about effects of long-term use on bone growth, though data are equivocal.) They do not compromise eligibility to participate in competition. These are usually indicated if symptoms are more persistent.

Preparations of cromolyn sodium, another anti-inflammatory agent, are not as potent as the steroids, but their greater safety may make them preferable as first-line agents for children.

Bear in mind that anti-inflammatories must be taken chronically to be effective, though some studies suggest that cromolyn preparations can be helpful if given just before exercise.

The use of antihistamines, decongestants, and parasympathetic agents for allergic rhinitis and beta2 agonists for asthma may be of great help, especially when they are used just before exercise or once the patient's respiratory symptoms start.

Patients who have anaphylactic-type reactions should wear medical alert identification and carry an adrenaline kit.

What is the role of over-the-counter preparations?
Over-the-counter (OTC) antihistamines effectively quell hay fever symptoms and can be taken regularly or occasionally. They are inexpensive and easy to use, but their sedating effects (reported by 20% to 35% of patients who take them) (8) may make them unacceptable to athletes. Even if such effects are subtle—indeed, imperceptible to the patient—they may materially impair athletic performance, particularly for highly trained athletes.

Drowsiness and fatigue reduce stamina. Reflexes, coordination, and cognitive skills are critical in many sports, and OTC antihistamines can have an impact on all of these. Often, patients are not aware of the impairment of their mental focus or coordination, which may last as long as the more obvious signs of sedation (9).

The slowing of reaction time that has been demonstrated with OTC antihistamines could, in theory, increase the risk of injury—a runner fails to see a pothole in time to avoid it, for example.

The side effects of OTC decongestants like ephedrine or pseudoephedrine resemble those of amphetamines and excessive caffeine: tremors or a jumpy, jittery feeling. The increase in blood pressure and heart rate associated with these drugs can be particularly problematic in patients over age 40.

In national or international competition, recent decongestant use, with its concomitant increase in blood pressure and heart rate, may be grounds for disqualification.

Which nonsedating antihistamines do you prescribe?
The lesser likelihood of sedation and cognitive impairment makes the newer prescription antihistamines a better choice for many athletes. But the risk of cardiac arrhythmias is a particularly critical issue in the context of strenuous activity. Terfenadine, which has been shown to cause arrhythmias when used in high doses and when prescribed in combination with certain other drugs (ketoconazole, itraconazole, cla-rithromycin, erythromycin, or troleandomycin), will soon be taken off the market, but is still available. It should be avoided. Though there is little evidence that the same is true for astemizole, its chemical similarity to terfenadine makes me cautious about its use.

There have been no reports of cardiac effects with loratadine, which is metabolized by several different pathways; and fexofenadine, a metabolite of terfenadine, bypasses the liver and should be safe. I prefer to prescribe these type of drugs when antihistamines are needed.

When do you recommend immunotherapy?
Immunotherapy (allergy shots) increases patients' tolerance of specific allergens. If exposure cannot be avoided, and medications do not control a patient's symptoms adequately, immunotherapy using extracts of ragweed, grasses, or other allergens to which he or she has demonstrated sensitivity may reduce symptoms of allergic rhinitis and may improve asthma. It is effective for systemic stinging insect reactions (eg, honeybee, wasp).

This approach, however, requires a substantial, extended investment of time and effort. A typical protocol involves injections once weekly for 3 to 4 months, then every 2 to 4 weeks for up to 5 years. The regimen may pose problems for athletes, particularly those who have an intensive practice schedule. Patients should be told to avoid strenuous activity for several hours after each injection, which might increase blood absorption, raising bloodstream allergen levels to a point where allergic symptoms develop and anaphylaxis might occur.

How do you manage allergic contact dermatitis?
Treatment is symptomatic. Wet compresses (lukewarm water or saline solution) are indicated for blistering rashes. Topical corticosteroids may be useful, but a brief course of systemic steroids or high-dose antihistamines is often necessary, particularly in severe cases.

Once the offending substance has been identified, it should be avoided: A change in athletic shoes or other equipment may be necessary. Find substitutes for antibiotic ointments or analgesic preparations to which the patient is sensitive.

A number of preparations have been developed that purport to protect sensitive people from poison ivy and oak, but most have not proven effective. Only one such product, Ivy Block (Enviroderm, Louisville, Kentucky) has been approved by the US Food and Drug Administration for the prevention of poison ivy. The bentoquatam 5% lotion hardens to form a claylike barrier.

References

Fitzgerald L: Exercise and the immune system. Immunology Today 1988;9(11):337-339
Peters EM, Bateman ED: Ultramarathon running and upper respiratory tract infections: an epidemiological survey. S Afr Med J 1983;64(15):582-584
Helenius IJ, Tikkanen HO, Haahtela T: Association between type of training and risk of asthma in elite athletes. Thorax 1997;52(2):157-160
Storms WW: Exercise-induced asthma in athletes: current issues (editorial). J Asthma 1995;32(4):245-247
Bleecker E: Exercise-induced asthma, urticaria, and anaphylaxis, in Lichtenstein LM, Fauci AS (eds): Current Therapy in Allergy, Immunology, and Rheumatology. St. Louis, CV Mosby Co, 1988, p 39
Fjellbirkeland L, Gulsvik A, Walle A: Swimming-induced asthma. Tidsskr Nor Laegeforen 1995;115(17):2051-2053
Fisher AA: Allergic contact dermatitis: practical solutions for sports-related rashes. Phys Sportsmed 1993;21(3):65-72
Naclerio RM: Allergic rhinitis. N Engl J Med 1991;325(12):860-869
Gengo F, Gabos C, Miller JK: The pharmacodynamics of diphenhydramine-induced drowsiness and changes in mental performance. Clin Pharmacol Ther 1989;45(1):15-21

Dr Blumenthal is a professor and director of the asthma and allergy program in the Department of Medicine at the University of Minnesota in Minneapolis. Carl Sherman is a contributing editor of The Physician and Sportsmedicine. Address correspondence to Malcolm N. Blumenthal, MD, University of Minnesota, 420 Delaware St SE, Box 434, Minneapolis, MN 55455.

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