Terms and Definitions

When you and your child are dealing with allergies and immune system disorders, you may hear medical terms you’re not familiar with. Some of the most common words you may come across include the following:

  • AIDS

acquired immunodeficiency syndrome.

  • Allergy

an overly sensitive immune system reaction to a specific substance, such as pollen, food or drugs, that does not cause symptoms in most people.

  • Anaphylactic shock

also called anaphylaxis, a severe and sometimes fatal immune system reaction to a substance such as a bee sting or penicillin.

  • Antibodies

immune system proteins that are able to counteract or get rid of foreign substances called antigens.

  • Antigens

substances that are foreign to the body and cause antibodies to form.

  • Asthma

an inflammatory condition of the bronchial airways that causes them to become over-reactive, producing increased mucus, swelling and muscle contraction.

  • Atopic dermatitis

also known as eczema, or an inflammation of the skin, this allergic reaction affects the skin with symptoms such as itching, redness and swelling.

  • Chronic infection

a disease that lasts for a long time or recurs frequently, such as ear infections that happen one after another or repeated instances of pneumonia.

  • Desensitization

the process of making an allergic person less reactive or non-reactive to certain triggers in the environment.

  • Environmental allergies

conditions such as asthma and hay fever that are brought on by an overly active immune system reaction to something in the environment such as pollen or dust.

  • Food allergies

allergic reactions that are brought on by an overly active immune system reaction to a specific food such as peanuts or shellfish.

  • HIV

human immunodeficiency virus.

  • Immune system

a collection of cells, chemical messengers and proteins that work together to protect the body from harmful micro-organisms, but can also lead to allergy and hypersensitivity problems.

  • Immunoglobulin

a protein that is able to act as an antibody.

  • Immunology

science that deals with the immune system.