Glossary of Terms

A Brief History of Allergy

The term, allergy was first coined in 1906 by the pediatrician, Clemensvon Pirquet.

He used the term to explain the “altered reactivity” some of his patients had to substances (“allergens”) that didn’t affect most other people. The concept, however, goes back much further, and we can be fairly certain that an allergic reaction was what the Roman philosopher Lucretius had in mind when he stated over 2,000 years ago that “One man’s meat is another man’s poison.”

The original meaning of “allergy” referred to any altered response to a substance.

By 1925 the majority of American allergists had accepted a narrower definition to describe an adverse immune system response.

Particularly one that could be scientifically demonstrated with the introduction of a substance, such as pollen, mold, animal dander, and dust, via a skin prick test.

The reactions recorded by this testing method have become our classic allergic conditions: allergic rhinitis and hay fever, asthma, eczema, hives, and the life-threatening cascade of symptoms leading to anaphylactic shock. In the 1960s, scientists discovered that the skin prick test was actually measuring the presence of an antibody. Read More….


Action-plan (for asthma): a plan devised by an asthmatic and his/her medical caregivers, to be put into action at predetermined signs of deteriorating breathing ability.

Acute (of a disease or disorder): having a sudden onset and a short, sometimes severe course.

Add-on (accessory) devices: tubes or small containers (also called “spacers”) added to metered-dose inhalers, allowing the aerosolized medication to be sprayed into the airways with less meticulous timing. Adrenalin: a hormone naturally produced by the body’s adrenal gland (especially in times of fear or stress) that increases the heart rate and constricts blood vessels. See also Epinephrine.

Adrenergic: activated by, characteristic of or secreting adrenalin (epinephrine), or substances with similar biological activity.

Aerosol: medication supplied as a fine mist.

Airway obstruction: a narrowing, clogging or blocking of the breathing passages.

Allergen: any substance —usually a protein — that creates allergic sensitization and induces an immunological reaction. See also Antigen.

Allergic reaction: immune-system overreaction provoked by contact with normally harmless substances such as pollen, moulds, foods or cosmetics.

Allergic rhinitis: an IgE-mediated allergic reaction involving inflammation of the nasal membranes, caused by an inhaled allergen such as polls animal debris or mould.

Allergist: a physician with specialized training in the body’s immune system, the science of immunology and allergy-related disorders.

Allergy: an inappropriate or overly strong response by the body’s immune system to normally innocuous substances, resulting in identifiable (some-times severe) symptoms.

Alveoli: air sacs at the ends of the lung’s bronchioles, where oxygen is absorbed into the bloodstream.

Anaphylactic reaction: a severe allergic response with rapid changes in many systems of the body, including widespread hives, swelling, airway block-age, breathing difficulty, blood-vessel expansion and “leakiness” — causing a sudden drop in blood pressure — which may lead to shock, collapse, heart stoppage and even death.

Anaphylaxis: an immediate, rapid, severe (possibly life-threatening) reaction involving many body systems at once.

Angioedema: swelling of the skin’s deeper layers.

Antibodies: special protein molecules (made by white blood cells) that bind to foreign particles (antigens) when they enter the body; the “allergy antibody,” immunoglobulin E (IgE), triggers allergic symptoms. Anticholinergic agent: a type of bronchodilating (airway-widening) agent used as an add-on medication for asthma.

Antigen‘ any foreign protein or other agent that, when introduced into the body, stimulates the production of antibodies. (Allergens are one type of antigen.)

Antihistamine: a drug that relieves some allergy symptoms by blocking the action of histamine.

Anti-inflammatory medication: a substance that reduces inflammatory swelling and discomfort. ASA (acetylsalicylic acid): a painkiller, fever reducer and anti-inflammatory agent used as an ingredient in many products — e.g., in headache remedies and some decongestants. Also called “aspirin” in the U.S. (In Canada “Aspirin” is a brand name for ASA.)

Asthma: a disorder in which the airways become inflamed, constricted and blocked by mucus. Symptoms are wheezing, coughing and shortness of breath.

Atopic: subject to Atopy.

Atopic dermatitis: see skin inflammation and allergies

Atopy: an inherited tendency to develop allergic disorders, with an oversensitive immune system that produces above-average amounts of IgE antibody.

Autonomic: involuntary or automatic — often applied to the part of the nervous system that acts without our conscious knowledge


Basophil: type of white blood cell in bloodstream that releases chemical mediators during an allergic reaction. B-cells: white blood cells, derived from bone marrow, that produce IgE antibodies — also called “B-lymphocytes.”

Beta agonist: a drug that stimulates the beta receptors — e.g., in lung tissue, expanding the airways to ease breathing. Beta blockers: drugs to reduce blood pressure.
Beta receptor: the site in certain body tissues that responds to stimulation by specific drugs and related substances.

B-lymphocytes: see B-cells.

Bronchi: large air passages leading from the trachea to the lungs.

Bronchial hyperactivity: extra-sensitive or “twitchy” reaction of the airways to stimuli such as cold air — linked to asthma. Bronchial tubes: tubes through which air passes from the nose and mouth into the lungs, and back out again.

Bronchioles: tiny, branching extensions of the bronchi inside the lungs.

Bronchitis: inflammation of the bronchi, arising from irritation or a viral or bacterial infection.

Bronchodilators: inhaled medications that relax smooth muscle and widen constricted air passages, making it easier for people with blocked airways to breathe.

Bronchospasm: contraction of the muscles encircling the airways, narrowing the breathing passages.


Challenge testing: a method of testing for food (or other) allergies in which the person is exposed to a tiny amount of the substance and symptoms are observed. In an “open” challenge, the person knows which substance is being tried; in a “blind” challenge, the presence or absence of the suspected allergen is disguised.

Chronic: tending to occur regularly over a long period. Conjunctivitis: inflammation of the conjunctiva — the membranes lining the eyelid — with swelling, itching, redness and watering of the eye.

Contact dermatitis: a skin rash triggered by touching or rubbing a material or chemical. Corticosteroids: natural or synthetic hormones used as anti-inflammatory agents in the treatment of allergic reactions and asthma.

Cytokines: chemical messengers secreted by lymphocytes (e.g., by TH2-helper cells) that cause other cells to react (e.g., cause B-cells to produce and release IgE antibodies).


Dander: tiny scales of animal skin and hair mixed with dried saliva.

Decongestant: a medication that reduces nasal congestion.

Degranulate: release mediator chemicals from granules of mast cells or basophils in response to an allergen invasion and IgE-antibody activity.

Desensitization: see Immuno-therapy.

Dilate: expand.

Dust mite: a tiny insect that lives on dead skin scales in house dust. Its faeces cause allergies.


Eczema: an itchy, non-contagious skin condition that can be flaky or wet and weepy. Eczema is sometimes due to an allergy (atopic eczema), but not always.

Emphysema: a chronic, irreversible lung disease characterized by a breakdown of the walls of the lungs’ alveoli.

Eosinophil: a white blood cell that is part of the body’s immune defenses; a collection of eosinophils at an attack site can cause an inflammatory reaction (as in an asthma attack).

Elevated numbers indicate an allergic reaction.

Epinephrine: adrenalin (often synthetic) taken by injection for the treatment of severe allergic reactions or anaphylaxis. The terms “epinephrine,” “adrenalin” and “adrenaline” are often used interchangeably.


Forced expired volume (FEY): the maximum volume of air that a person can forcibly breathe out of the lungs in a certain time (usually one second), after taking in a full breath.

Fungal: pertaining to or caused by fungus.

Fungus: organisms such as yeast, mushrooms and moulds.


Hapten: a molecule in the body that may attach to small allergens.

Hay fever: seasonal allergic rhinitis, which causes nasal discomfort, itching, swelling, congestion and a clear discharge —usually triggered by pollens from trees, grasses or weeds.

HEPA filters: high-efficiency particulate air filters for air-conditioning and heating units, to curb indoor allergen levels. Histamine: an organic chemical or “mediator” released by mast cells and basophils in an allergic reaction, responsible for much of the swelling, itching and allergic discomfort.

Hives (urticaria): itchy skin weals with white, raised areas surrounded by redness. Can look like a cluster of mosquito bites, or appear as large welts.

Hypersensitivity: overreaction to normally harmless stimuli or substances.

Hypoallergenic: containing lower than usual amounts of allergen — but not necessarily allergen-free.


IgE antibody: an antibody normally made in small amounts, but manufactured inappropriately by allergy-prone people. IgE antibodies attach to mast cells and basophils and trigger the mediator release that produces allergic symptoms. IgE-mediated: occurring because of IgE-antibody activity.

Immune system: a collection of cells and chemicals in the body that defends it against attack or invasion by foreign materials such as viruses, bacteria, fungi, parasites and poisons. The immune system guards the body against foreign, disease-producing substances. Its “workers” are various white blood cells Including one trillion lymphocytes and 100 million trillion antibodies produced and secreted by the lymphocytes. Lymphocytes are found in high numbers In the lymph nodes, bone marrow, spleen, and thymus gland.

Immunoglobulin: protein molecules that act as antibodies and are part of the body’s immune defences. There are different types (immunoglobulin A, G, E and so on). Immunoglobulin E (IgE) is the allergy antibody.

Immunotherapy: a series of injections of allergen extracts —commonly referred to as “allergy shots” or “desensitization” — aimed at abolishing or dampening the reaction to specific allergens.

Inflammation: tissue swelling, redness, heat and pain — the result of fluid leaking out of blood vessels into the surrounding area.

Inhalant allergens: allergens that enter the body through the nose, such as dust, pollen, animal dander and moulds. Inhaler: a device to provide medications inhaled into the lungs as aerosolized drops or powder.

Irritant: anything that irritates or worsens symptoms. Cold air can act as an irritant that sets off an asthma attack; cosmetics can irritate the skin.


Late-phase: the stage of symptoms that occurs several hours after exposure to an allergen, as opposed to immediate allergic responses.

Leukocytes: white blood cells.

Leukotrienes: biologically active compounds, released by mast cells and basophils, that act as mediators in an allergic response, contracting smooth muscle: e.g., constricting the airways.

Lymphocytes: specialized white blood cells that participate in immune and allergic responses; part of the body’s defense system


Macrophages: large white blood cells that act as “scavengers,” engulfing microorganisms and antigens.

Mast cells: cells in the mucous membranes that release chemicals called mediators (such as histamine, bradykinin, leukotriene), which cause the symptoms typical of allergic reactions.

Mediators: potent chemicals released from basophils and mast cells, responsible for the symptoms of allergic disease.

Metered-dose inhaler (MDI): a small, sometimes pressurized canister that dispenses aerosol medications, often used for asthma.

Mucosal tissue: soft layers of lining tissue just below the skin’s surface, and in the respiratory tract and digestive tract, containing many mast cells.

Mucous membrane: see Mucosal tissue.

Mucus: phlegm, or slimy discharge from mucosal tissue.


Nebulizer: a device requiring a power source and compressor to deliver a mist of aerosolized medication, usually through a mask; used in some asthma cases.

NSAIDs: Nonsteroidal anti-inflammatory drugs.


Peak flow meter: a hand-held device with a mouthpiece and spring gauge to measure the force with which someone can expel air from the lungs, to determine the extent of obstruction.

Prostaglandins – lipid autacoids derived from arachidonic acid. Prostagladins sustain homeostatic functions and mediate pathogenic mechanisms, including the inflammatory response

Pulmonary: having to do with the lungs.


Radioallergosorbent test (RAST): a blood test that measures the level of IgE antibodies to a particular allergen.

Respiratory tract: the passages of the breathing apparatus, including mouth, nose, throat, windpipe, bronchi and lungs.

Rhinitis: inflammation of the mucous membranes lining the nose, with itching, swelling, congestion and a clear discharge.

Rhinoconjunctivitis: inflammation, redness, itching, watering and discharge in both nose and eyes.


Seasonal allergic rhinitis: see Hay fever.

Sensitization: allergic sensitivity caused by exposure to a specific allergen, leading to a reaction on re-exposure.

Serum sickness: a complex reaction (often to drugs) with a rash, fever, swelling of the face, eyelids or lips, puffiness in the hands and feet, and joint pain.

Skin prick test: an allergy test that involves pricking or scratching the skin on parts of the back or arms, applying a drop of allergen-containing solution and observing the reaction. A reddened spot indicates a positive reaction.

Spacers: assorted tubes or chambers attached to pressurized metered-dose inhalers to ease medication delivery.

Spirometer: an instrument that measures the flow of air in and out of the lungs.
Sputum: secretion from the lower passages of the lungs, expelled by coughing.
Stimulus: any agent, act, event or influence that produces functional changes in the body. Sulfites: a group of food additives (e.g., metabisulfites) that can cause allergies or exacerbate asthma.

Systemic: a reaction that spreads to affect many body systems at once, usually involving the blood circulation and breathing system.


T-cells: white blood cells that are processed in the thymus gland, and participate in cell-mediated immune-system responses.

T-helper cells: a type of lymphocyte (white blood cell) involved in the body’s immune defenses.

TH1-helper cells: specific lymphocytes that primarily make interferon, an anti-viral agent.

TH2-helper cells: specific lymphocytes that secrete cytokines (chemical messengers) that incite B-lymphocytes to make IgE antibodies.

Tolerance: the ability to encounter a certain amount of allergen or irritant without reacting adversely.

Topical: (of a medication or other substance) — applied to a surface area or specific site, such as the skin or the nasal passages.

Total allergy syndrome (“20th-century disease”): a term now largely replaced by “multiple chemical sensitivity,” to denote sensitivity — but not proven allergy — to multiple environmental agents.

Trachea: the windpipe —extending from the larynx to the two bronchi.

Twentieth-century disease: see Total allergy syndrome.

Type 1 allergic reaction: immediate or fast-onset allergic reaction that involves IgE-antibodies.


Urticaria: see Hives.


Vasoactive: affecting the vascular (blood-vessel) system. Vasoconstrictor: an agent or medication that constricts the blood vessels.


Wheezing: a whistling sound when someone breathes out through narrowed or inflamed bronchial tubes; a frequent sign of asthma.

Medical History of Allergens

As mainstream medicine took a progressively more restrictive approach to allergy diagnosis, several physicians, including Theron Randolph, M.D., began investigating largely overlooked sources of adverse reactions, particularly food and chemical agents.

They found that IgE was not involved in all types of adverse reactions, especially those that occurred hours or days after exposure to a food or environmental substance. Conventional medicine frowned upon what they construed as an aberration of allergy research, and food manufacturers, some of whom were funding allergy research, were wary of their products being implicated in allergies.’

Despite discouragement from mainstream medicine and special interest groups, respected physicians such as Dr. Randolph continued to research and validate the existence of “hidden” or “latent” food and environmental reactions, calling them “sensitivities” and “intolerances” to distinguish them from antibody-antigen allergies.

These doctors taught that sensitivity reactions to commonly eaten foods could cause a range of symptoms in susceptible individuals, including headaches, eczema, fatigue, arthritis, depression, and various gastrointestinal disorders. Their research further revealed that chemicals in the environment could have profoundly negative effects on the body.

In 1962, Dr. Randolph published the first textbook in the nascent field of environmental medicine Since then, may other physicians have followed in Dr. Randolph’s footsteps, educating the public that the widespread use of insecticides, herbicides, formaldehyde, plastics, food additives, petroleum products, and other chemicals can—and does—lead to sensitivity.

Among the most debilitating is a multiple chemical sensitivity called environmental illness, of which fatigue, memory loss, and an inability to concentrate are major symptoms.
Allergy will refer to an antibody-antigen reaction. Sensitivity and intolerance will refer to non-antibody-mediated events. However, since both types of reactions are caused by many of the same underlying factors, alternative medicine practitioners often use the same therapies and strategies to eliminate allergy as well as sensitivity.