Definition

1. Noun:
   • An immediate hypersensitivity reaction: A type of allergic reaction, also known as Type I hypersensitivity, mediated by immunoglobulin E (IgE) antibodies. The reaction becomes apparent in a sensitized person within minutes of contact with a specific allergen.

Usage

• The term "atopic allergy" is used in medical and scientific contexts to describe a specific, rapid immune response to an allergen (e.g., pollen, dust mites, certain foods, animal dander) in individuals with a genetic predisposition (atopy).
• It is a formal term. In common language, people often simply say "allergy" or specify the type, such as "hay fever" or "food allergy," which are typically atopic allergies.

Examples

• Noun:
  • The patient's history of eczema and asthma suggests a predisposition to atopic allergy.
  • Skin prick testing is a common method for diagnosing an atopic allergy to specific substances.
  • Her severe reaction to peanuts was diagnosed as an atopic allergy.

Advanced Usage

• "Atopic" refers to the genetic tendency to develop allergic diseases. Therefore, "atopic allergy" specifically denotes an allergy occurring in an atopic individual.
• The reaction involves mast cells and basophils releasing histamine and other chemicals, leading to symptoms like sneezing, itching, hives, or, in severe cases, anaphylaxis.

Variants and Related Words

• Atopy (n): The genetic predisposition to develop allergic diseases such as allergic rhinitis, asthma, and atopic dermatitis (eczema).
  • Atopy often runs in families.
• Atopic dermatitis (n): A chronic inflammatory skin condition common in people with atopy.
  • Infantile eczema is a form of atopic dermatitis.
• Immediate hypersensitivity (n): A technical synonym for the rapid allergic reaction characteristic of atopic allergy.
• Type I hypersensitivity (n): The immunological classification for atopic allergy.

Synonyms

• Immediate allergy
• IgE-mediated allergy

Related Phrases / Idioms

• (To have) a classic atopic triad: A phrase sometimes used in medicine to describe a patient who has three common atopic conditions: eczema, allergic rhinitis (hay fever), and asthma.
  • The child presented with the classic atopic triad.

Noun

1. an allergic reaction that becomes apparent in a sensitized person only minutes after contact