Blowin' in the wind

May 1, 2002
Allergy-prone patients present particular challenges.

by Cathy Alty, RDH

Allergy-prone patients present particular challenges. Hygienists must be alert to triggers and treatments for allergic reactions.

Aah-choo! The level of patients with allergies is reaching epidemic proportions. Individuals can have an allergic reaction to nearly any given substance ... foods, plants, animals, insect stings, molds, latex. According to the American Academy of Allergy, Asthma, and Immunology (AAAI), allergies affect 40 to 50 million people and are the sixth-leading cause of chronic illness in the United States. As the numbers of people with allergies, uh, swell, so do the challenges of health-care providers to treat these patients without offending their various sensitivities.

What are allergies and what causes them? What are typical allergic reactions? Are there any allergies that are of particular concern in dental treatment?

The Asthma and Allergy Foundation of America (AAFA) defines an allergy as the immune system's exaggerated response to a foreign - usually harmless - substance. When a person with an allergy comes in contact with the allergen, their immune system reacts as if the substance is harmful. The body's mast cells release inflammatory chemicals that cause itching, swelling, watery nose and eyes, asthma, wheezing and coughing, or hives. Sometimes the patient's eosinophils join in and secrete even more inflammatory chemicals. If enough inflammatory chemicals are released, a reaction throughout the body may trigger hives or decreased blood pressure, which may be life-threatening.

Common allergens are pollen, dust mites, molds, animal dander, foods, chemicals, latex, and insect venom. Allergic reactions often are unexpected and unidentified. More than half of all allergy sufferers fail to recognize their symptoms at first, falsely assuming they have a cold or the flu. Sensitivity can change over time; new allergies can develop at any age. Scientists believe that repeated exposure to an allergen may induce allergic symptoms. It is often difficult to determine exactly what allergen is the trigger, but the symptoms are focused in three areas: the skin, eyes, and/or lungs. The skin may break out in a rash or hives, and the eyes will water. The lungs secrete fluid, and the muscles and bronchial tubes may tighten and swell, causing coughing or wheezing. Asthma is strongly linked to allergies, and an asthma attack can be triggered by exposure to an allergen.

Irritants can sometimes be mistaken for allergies. People think, for example, they're allergic to cigarette smoke because their reaction to these irritants is similar to an allergic response. Allergy experts tell us that noxious smells, like cigarette smoke or airborne perfume, are not classified as allergens; however, their irritant effect can worsen active allergy symptoms. To discover if a person is truly allergic to a substance, the potential allergen can be put on the skin and tested. If the a skin reaction occurs, you are allergic to that substance.

Dr. Greg Redding, pediatric pulmonologist at Children's Hospital and Medical Center in Seattle, says that the fight against allergic reactions begins in the bedroom. Dr. Redding says that because we spend one-third of our time in the bedroom sleeping with a vulnerable, open airway, dust and animal dander must be controlled in this room. He suggests keeping windows closed and humidity levels in the home low to prevent dust mites from thriving. Covering mattresses and pillows as well as reducing room dust levels and dust collectors (like stuffed animals) is also beneficial.

Allergic patients can be a challenge for the hygienist. It is important to be aware of the allergy, how a patient may react to an allergen, and what we can do to help. Allergic reactions range from mild to severe (anaphylaxis). Antihistamines are usually sufficient for patients with milder reactions, such as runny nose and itchy eyes. More severe reactions - when patients are having trouble breathing or going into shock - may require epinephrine and even a call for emergency medical services. Many allergic patients take prescription antihistamines or receive immunotherapy (allergy shots) to help reduce their symptoms.

Latex allergy is a new but important concern in the health care world. Dr. Lauren Charous, of Milwalkee, Wis., a physician who specializes in latex allergy, estimates that 5 to 12 percent of health care workers who are regularly exposed to latex may develop symptoms of latex allergy. These symptoms may begin with acute itching or hives on gloved skin, but can progress to "hay fever" or asthma in affected personnel. Employees with latex allergy should avoid using any latex gloves since it may intensify their sensitization or trigger an acute reaction. Avoidance measures, however, are not sufficient protection, since latex aeroallergen generated from powdered latex gloves readily disperses within dental offices. Fortunately, substitution of nonlatex or nonpowdered latex gloves results in predictable and rapid disappearance of detectable latex aeroallergen.

Some health-care workers mistakenly believe they are allergic to latex due to problematic skin rashes on their hands. In most cases, "chapped hands" rashes that occur over the knuckles are nonspecific irritant dermatitis induced by frequent hand-washing and use of gloves. In some cases, individuals may develop a "skin allergy" to one of the chemicals used in rubber manufacturing. This type of allergy, while annoying, is never life-threatening.

Dental patients also can have latex allergy. Those at risk include individuals with frequent surgeries in early infancy, multiple allergies to fresh fruits and vegetables that are known to cross-react with latex (for example, bananas, avocado, kiwis or hazelnuts), or history of occupational latex exposure. Before any procedures, it is wise to ask patients about any prior reactions to latex during previous dental or gynecologic exams, or to powdered latex products such as balloons or latex gloves.

Other sources of allergy in the dental office are acrylic, local anesthetic, antibiotics, and metal allergies. Most reactions with acrylic are caused by contact with the free monomer. Avoiding the use of uncured acrylic directly in the mouth will help prevent an allergic reaction. Any drug can cause an allergic reaction, but some have higher allergic potential. The AAFA states that an estimated 42,000 cases of adverse drug reactions are reported annually.

Preservatives in anesthetics are one culprit; many anesthetics are now preservatives-free. Some patients are allergic to the "-caine" drugs (para-aminobenzines), so their use in someone with a history of allergies may be contraindicated. Be sure to check the label on topical anesthetic before using on an allergic patient. Topical anesthetics tend to cause more allergic reactions than do local anesthetic injections. How do we know if a person with no prior history is experiencing a first-time allergic reaction? Physicians tell us that any unexpected reaction from a patient receiving a drug should suggest a drug allergy. The only way to know for sure is to "rechallenge" the body, which is something best left to the experts.

Prescribed antibiotics for patients with infection or premedication needs can be a source of allergic reaction. Use of drugs with low potential for allergic reaction should be selected over those with a greater potential in allergic patients.

The metal allergies most reported include nickel, mercury, gold, and cobalt. Other metals used in dentistry may cause sensitivities in some patients.

Multiple Chemical Sensitivity (MCS) is a disorder that is triggered by exposures to chemicals. The National Institute of Environmental Health Sciences say many in the medical community, including the Centers for Disease Control and the American Medical Association, do not accept MCS as a genuine medical disorder. Some physicians do acknowledge there is a link, but conclusive scientific evidence is lacking. Symptoms are allergy-like with additional symptoms of fatigue, memory loss, confusion, headache and muscle and joint aches.

Allergic patients are increasing in numbers. It is our responsibility to prevent allergic responses as best we can when they are in our care.

Cathleen Terhune Alty, RDH, is a frequent RDH contributor based in Clarkston, Michigan.

Types of latex product reactions:

Irritant contact dermatitis - Not a true allergy, and the least threatening type of latex reaction. Causes dryness, scaling, itching, burning and skin lesions.

Allergic contact dermatitis - Causes reactions identical irritant contact dermatitis; however, reactions are more severe and last longer. It is believed this reaction is due to additives used in latex processing.

Immediate allergic reaction (latex hypersensitivity) - The most serious reaction to latex. Symptoms include stuffy or runny nose, hives, and severe itching. In rare instances, it may progress to low blood pressure, difficulty breathing, chest pain, rapid heartbeat, anaphylactic shock, loss of consciousness, or even death.

- information courtesy of the Health Information Center at the Cleveland Clinic

Additional resources

• Allergy Management Center: www.theallergyre

• American Academy of Asthma, Allergy and Immunology (AAAI):

• American Academy of Pediatrics:

• Asthma and Allergy Foundation of America (AAFA):

• Food Allergy Research and Resource Program:

• National Institute of Allergy and Infectious Diseases:

• Info on Multiple Chemical Sensitivities: http://

Latex allergy and food cross-allergy

The following foods can trigger an allergic reaction to someone allergic to latex because the proteins in them mimic latex proteins as they break down in the body. Likewise, persons who are allergic to these foods may have an undiagnosed cross allergy to latex. Allergy experts recommend that latex allergic individuals be evaluated for sensitivity food allergies. ! Bananas ! Celery ! Avocados ! Carrot ! Potatoes ! Hazelnut ! Kiwi ! Chestnuts ! Papaya ! Figs ! Pineapple ! Grape ! Tomato Stone Fruits, inlcluding: peaches, plums, cherries, nectarines