Allergy triggers

What triggers an allergy?

An allergy attack occurs when an allergen enters the body. Once in the body, the allergen triggers the immune cascade that releases histamine, resulting in allergic symptoms. Allergens reach the body through inhalation, injection (such as an insect bite or sting), ingestion or skin contact.

Common allergens include:

  • Air-borne pollen causing hay fever
  • Allergies from pets and animals
  • Dust-mite allergies
  • Allergies to household mould
What happens during an allergic reaction?