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Glossary of Allergy & Asthma Terms

Adrenal Failure
When the adrenal glands fail to function, for example in a patient that has been taking daily oral prednisone for a very long time, the patient can no longer produce adequate cortisol. If the patient is stressed and the body cannot react by producing cortisol, there is a risk that the patient's blood pressure may drop and he/she may enter into a shock-like state. Asthmatic patients who suffer adrenal failure are at high risk for a very severe asthmatic attack which is potentially fatal if they do not receive supplemental corticosteroid medication in a timely fashion.

Adrenal Glands
Tiny glands that are found on top of each kidney. They secrete hormones called glucocorticosteroids (cortisol) and mineralocorticoids (aldosteroids). The glucocorticosteroids are important in the body's metabolism and have potent anti-inflammatory effects. The production of glucocorticosteroids is necessary for the body to function properly.
Allergens Substances which cause abnormal sensitivities and allergic reactions, such as pollens, molds, and dust mites.
Allergic Rhinitis Redness, swelling, and itchiness in the nose caused by an allergic reaction. Seasonal allergic rhinitis is known as hayfever.

A specially trained physician who treats individuals suffering from allergy of the eyes, nose, throat, and sinus; asthma and other lung disease, allergic skin disorders (poison ivy, eczema, etc.); and problems of the immune system (frequent infections). An allergist also evaluates and treats individuals with drug allergy, insect reactions, food allergy, autoimmune disorders (lupus, vasculitis), and allergy to materials in the work environment. The physicians at The Asthma Center are Board Certified Allergists and Clinical Immunologists. This means the doctors have completed 4 years of medical school, 3 years of residency in Internal Medicine or Pediatrics, and 2 or more years of specialized training in Allergy and Immunology at leading medical institutions. In addition, the doctors have passed certification examinations for Allergy and Immunology as well as Internal Medicine or Pediatrics. All are certified by the American Board of Allergy and Clinical Immunology as well as the American Board of Internal Medicine of Pediatrics.

An abnormal sensitivity based on the reaction of the body's immune system to a substance or substances which are generally harmless to others.
Antihistamine A medication which decreases the body tissues response to histamine (some antihistamines cause drowsiness).

A disease characterized by reversible narrowing and inflammation of the bronchial tubes often accompanied by wheezing, shortness of breath, and/or coughing.

Beta 2 Agonists (B-2 Agonists)
Medications of the sympathomimetic class (e.g. albuterol) that are used in the treatment of asthma. These bronchodilators work by selectively stimulating the Beta 2 receptors on the bronchi to cause bronchodilation. Older sympathomimetic inhalers also stimulated the Beta 1 receptors of the heart often causing the side effect of a racing heart beat.

Challenge Test
A medical procedure used to identity those substances to which a person is sensitive by deliberately exposing an individual to dilute amounts of those substances until allergic symptoms are provoked.

Chemical Mediator
These are substances released from mast cells as well as other cells lining the bronchial tubes and the mucosal membranes of the eyes and nose that cause allergic or asthmatic symptoms. They include histamines, leukotrienes, and other chemicals that can result in congestion, swelling of tissues, mucus production, bronchospasm, itchiness, and inflammation.

Corticosteroids (glucocorticosteroids or steroids)
One of many types of steroids secreted by the adrenal gland and also manufactured for use as a powerful medication in the treatment of inflammatory reactions such as that occurs in asthma and allergy.

DPI (dry powder inhaler)
DPI is a device to deliver asthma medication by the inhaled route in which the medicine is in a dry form. Asthma medication can be inhaled so that they go directly to the lungs and by-pass the rest of the body thus decreasing side effects. Inhaled medications can be administered as a DPI, which has the advantage of being breath-activated.

Gastoresophageal Reflux Disease (GERD)
GERD occurs when acid in the stomach leaks past the upper stomach valve and rises up the esophagus.

Hayfever See "Allergic Rhinitis"

A substance produced by the body in reaction to exposure to allergens; it causes eyes to tear and itch, nasal passages to swell, the nose to run, and sneezing to occur.

Hives See "Urticaria"

IgE(Immunoglobulin E)
IgE is one of 5 human antibodies and is important in causing allergic symptoms. The IgE antibody attaches selectively to mast cells lining the respiratory mucous membrane, gastrointestinal tract, and skin. When the part of the IgE antibody is exposed to its matching allergen, then the mast cell is stimulated to release chemical mediators that cause allergic symptoms.

Immunoglobulins are antibodies that fight disease by damaging foreign organisms that invade the body. Certain immunoglobulins such as IgG and IgM act as a primary defense against invading bacteria. Deficiency of these antibodies can result in recurrent infections, which can provoke recurrent asthmatic symptoms, ear infection, sinusitis, and pneumonia. Increased levels of IgE are usually associated with allergy symptoms.

A treatment for hayfever and allergic-type asthma that involves periodic injections of the allergens (such as pollens, molds, and dust mite) that are causing the allergic reaction or asthmatic attacks. The injections, commonly called allergy shots, work to build up an immunity to the allergens and help prevent attacks of hayfever or asthma.

Mast Cells
Mast cells are uniquely rich in chemical mediators that when released, either as a result of an allergic reaction or for any reason, can cause edema, itching, bronchospasm, and inflammation. They line the mucous membranes of the bronchial tubes, respiratory mucosa of eyes, nose, sinus, and intestinal tract. The skin is also rich in mast cells. The mast cells have special receptors for IgE and play central role in allergic reactions and asthma.

MDI (metered dose inhaler)
MDIs contain asthma medication in a liquid form in which the patient inhales a precise dose of medication mist from the device directly into the lungs. MDIs required good coordination during inhalation or the use of a spacer device.

Breaks down and eliminates.

Parasitic, microscopic plants without stems, roots or leaves. Molds are found outdoors in soil, vegetation and rotting wood. Indoors, they are often found in attics, bathrooms, basements, and in and around plants. Mold is also known as mildew.

PEFR (Peak Expiratory Flow Rate)
PEFR represents the maximum rate of flow of air you can blow out which is one way of measuring the function of your lungs. Asthma patients who are have some airway obstruction will notice that their PEFR measurements will begin to decrease as symptoms get worse.

PEFR Variability
Defined as the difference in measurement between the value of the PEFR take in the morning and the one taken in the evening. Usually the morning rate is somewhat lower than the evening rate. As one's asthma gets out of control, the PEFR variability increases.

The male fertilizing agent of plants that consists of microscopic, powdery granules.

Pollen Count
A measure of the pollen grains or mold spores in the air. Pollen counts are reported in the number of pollen grains or mold spores per cubic meter of air per 24 hours.

Pulmonary Function Test
An objective measure of lung function performed by an individual breathing into specialized equipment.

Sinusitis means inflammation of the sinus(es). Sinusitis can result from allergy, infections, or even chemical exposure. Patients with sinus disease often complain of nasal and head congestion, headaches, and post nasal drip.
Skin Tests Application of a small dilute amount of allergens to the skin through a scratch or injection. If the individual is allergic to that substance, a small raised area surrounded by redness (hive) will appear at the test site within 15 minutes.
Spacer A spacer is a tube-like device that is placed between the MDI (inhaler) and your mouth. It allows the inhaled medicated mist to slow down after you activate the MDI so that it can be inhaled more efficiently even if the patient coordination in using the MDI is not perfect.

The reproductive cells of molds.

Steroid Dependent
If you receive daily doses of corticosteroids over time, you can lose your ability to secrete cortisol from your adrenal gland in the natural way. If you are on long term daily cortico- steroids, you may have shrunken adrenal glands, and it may take months to years, if ever, to regain the ability to function normally once daily treatment is discontinued.You are at steroid risk when your asthma flares or whenever you are stressed since you can no longer produce the life sustaining corticosteroid levels that are necessary.You must self-administer supplementary corticosteroid treatment with every flare of asthma or stressful situations under your physicians' guidance.

Sympathomimetic(s) asthma medications (e.g. adrenalin, albuterol and psuedoephedrine) are used as either bronchodilators in asthma or decongestants in eye, nose, and sinus allergy. Modern sympathomimetic asthma medications are usually selective in that they stimulate mostly the beta 2 receptors in the lung causing bronchodilation (e.g. albuterol). While those sympathomimetics used to treat upper respiratory allergy also stimulate alpha-receptors causing the blood vessels to contract and thereby decreasing congestion due to allergic reactions ( e.g. pseudoephedrine, phenylpropolamine).

A reaction in the skin marked by swelling, redness, and itching. This reaction is known as hives.

Project Allergy would like to thank Dr. Irene Haralabatos from Allergic Disease Associates - The Asthma Center for allowing us to reprint from their published book on allergies and asthma.

For more information or to make a donation to their research fund, please contact The Asthma Center Education and Research Fund at 215-569-1111 or