Latex Allergy

What Is It?

A latex allergy is a hypersensitivity to latex, which is a natural substance derived from the milky sap of the rubber tree. Like any type of allergy, latex allergies arise when the immune system, which normally guards the body against foreign invaders (such as bacteria, viruses and toxins), reacts to an otherwise harmless substance, called an allergen. In the case of latex allergies, a person can have a reaction to the chemical additives used in manufacturing the latex products or to proteins in the latex itself. When the immune system detects the allergen, the antibody immunoglobulin E (IgE) is produced, triggering the release of chemicals within the body. One such chemical is the inflammatory agent called histamine. Histamine is partly responsible for the redness, itching and swelling of an allergic reaction, and it produces such symptoms as hives, rashes, a runny nose, and watery, swollen eyes. More seriously, it can lead to breathing difficulties and a severe allergic reaction called anaphylaxis that can include a sudden drop in blood pressure, an increase in pulse, and tissue swelling.

Latex is a flexible, elastic and relatively inexpensive material used in a number of healthcare and consumer products. Because it forms an effective barrier against infectious organisms, latex is used to make hospital and medical items, such as surgical and examination gloves and some parts of anesthetic tubing, ventilation bags, respiratory tubing and intravenous (IV) lines. In addition, it is used in making countless consumer products, including balloons, condoms, diaphragms, rubber gloves, tennis shoe soles, nipples for baby bottles and pacifiers, toys, rubber hoses and tires. Seven million metric tons of latex are used in manufacturing each year.

There are two forms of latex allergies. The first involves an immunological reaction, not to the latex itself, but to the chemical additives used in the manufacturing process. This type of allergy usually is seen in people who wear latex gloves regularly as part of their work. The second type of reaction, recognized only since the late 1970s, involves a reaction to the plant proteins in the latex itself.

As the use of latex products increases, so does the incidence of latex allergies. With the AIDS epidemic and increased precautions, latex examination gloves are used routinely when handling body fluids. Today, anyone who might come into contact with a person's body fluids wears protective gloves. As a result, health care workers are at increased risk of developing a hypersensitivity to latex products.

In addition to health care professionals and other workers whose occupations expose them to latex, people who undergo repeated surgical procedures are at a higher risk of developing latex allergies. For example, children born with spina bifida a birth defect in which bones that normally cover the spinal cord do not form properly are exposed repeatedly to latex products in connection with frequent medical and surgical procedures. About 50% of children with spina bifida develop a latex allergy.

People can become sensitized to latex as a result of direct contact with natural rubber products. Inhaling latex particles is a common way for health care workers to become sensitized to latex. Many medical gloves are coated with cornstarch to make them easier to pull on and off. Cornstarch absorbs the latex proteins, and then carries them into the air where they can be inhaled.

Although most allergic reactions to latex involve only annoying symptoms such as itchy rashes and redness, latex allergies should be taken seriously. In more serious cases, when exposure levels are high, severe asthma and even anaphylaxis can occur.

Symptoms

As with any type of allergy, the first exposure to latex allergens usually does not cause any reaction. However, this first exposure can sensitize the immune system to the specific allergen, which can cause noticeable symptoms after later exposures.

When the sensitivity is to the chemical additives used in manufacturing rubber latex, the reaction typically occurs one to two days after exposure and usually involves a form of contact dermatitis, a rash that resembles poison ivy. The skin is usually red, cracked and blistered. When the sensitivity is to the latex protein, more serious symptoms tend to occur within minutes of exposure, and include hives, runny nose (allergic rhinitis) and allergic asthma. In rare instances, this type of allergy can cause anaphylaxis, a severe allergic reaction that can include a sudden drop in blood pressure, an increase in pulse, difficulty breathing and tissue swelling. Without prompt and proper treatment, anaphylaxis can lead to unconsciousness and, rarely, death.

Diagnosis

Your doctor may suspect that your symptoms are related to a latex sensitivity if you have a history of exposure followed rapidly by the appearance of symptoms. If you have other allergies and allergic conditions, including asthma, hay fever and eczema (atopic dermatitis), you may be more susceptible to latex allergy. There also seems to be a link between latex allergies and allergies to certain foods, including avocados, bananas, kiwi, pineapples, tomatoes and chestnuts.

A detailed medical history, coupled with a blood test called RAST, can help to determine your sensitivity to latex. The RAST measures the amount of specific IgE antibodies in the blood. Skin testing for latex allergy also can be done. In some cases, challenge tests with latex products are used to confirm the diagnosis. In a challenge test, you stay away from the suspected allergen for a period of time, then are exposed to the substance to see if you develop symptoms.

Prevention

The best way to prevent any type of allergy is to avoid exposure. With latex allergies, that means using gloves not made of latex for dishwashing or other chores, refraining from blowing up balloons, avoiding rubber bands and using condoms made of materials other than latex. You also should tell your health care providers so that they can avoid exposing you to products that contain latex. But if you work in the health care field, avoiding latex can be trickier. Many medical products contain latex. Although you may not be able to avoid latex completely, you may be able to limit the use of latex products and find products that are less irritating.

The amount of latex allergens shed by different types of gloves, for example, varies tremendously. Some contain less of the chemical additives that have been shown to cause skin sensitivity. A number of successful lawsuits involving latex reactions have prompted many manufacturers to change the way they make latex products. Because latex gloves that are powdered with cornstarch appear to cause the most problems, using nonpowdered gloves may help to prevent reactions.

Treatment

The most important treatment for occupational latex allergies is to avoid repeat exposures, which can increase sensitivity. This can mean asking to be reassigned in your work duties or even considering a change of occupations.

Once you have a reaction to latex, treatment depends on the type and severity of the reaction. An antihistamine can block the actions of histamine, which produces itching and swelling. Corticosteroid drugs, which are powerful anti-inflammatory agents, are used for more severe symptoms. These are available as tablets, nasal or bronchial sprays or topical creams. Although corticosteroid medications can be very effective against allergic reactions, they can produce serious side effects when used in high dosages or over long periods of time. Your doctor will weigh the benefits against the risks of side effects, and prescribe corticosteroids, if necessary, in the lowest effective dosage.

Anaphylaxis, the most serious allergic reaction, can cause blood vessels to dilate and air passages of the lungs to narrow, leading to wheezing, breathing difficulties and a drop in blood pressure. In the most severe cases, loss of consciousness and death can occur. Treatment for anaphylaxis involves an emergency injection of epinephrine (adrenaline) and rapid administration of intravenous fluids.

Talk to you doctor, and if you are at risk of such a reaction, consider carrying an emergency epinephrine kit, and learn how to use it.

When To Call A Professional

If you suspect latex allergies, a medical evaluation is needed to establish the diagnosis and provide guidelines about appropriate precautions.

Call your doctor if any of the symptoms persist or fail to respond to treatment. If you experience difficulty breathing, a rapid pulse, facial swelling or dizziness, contact your doctor or go to an emergency room at once. These symptoms could signal anaphylaxis, which requires emergency treatment.

Prognosis

With prompt, appropriate treatment, most people recover completely from an allergic reaction to latex. In rare cases, an allergic reaction to latex can be severe, leading to anaphylaxis and death. The outlook is better if latex is strictly avoided.

Additional Info

American Academy of Allergy, Asthma & Immunology (AAAAI)

555 East Wells St.

Suite 1100

Milwaukee, WI 53202-3823

Phone: (414) 272-6071

Toll-Free: (800) 822-2762

E-Mail: info@aaaai.org

http://www.aaaai.org/

National Institute for Occupational Safety and Health

4676 Columbia Parkway

Mail Stop C-18

Cincinnati, OH 45226

Toll-Free: (800) 356-4674

Fax: (513) 533-8573

http://www.cdc.gov/niosh/