What is an Allergy ?
Allergy is a hypersensitivity reaction initiated by immunological mechanisms; in other words an allergy is an abnormal response of the body’s immune system to some substances in the environment that are harmless for most people. These substances are called allergens.
An Allergic individual’s immune system mistakenly identifies these substances as a ‘threat or enemy’ and start an inappropriate/abnormal reaction while others identify it as harmless.
This reaction can be local or systemic; progressive and different immunological mechanisms involved. These mechanisms in an allergic individual can lead to an initial sensitisation to one or more allergens, followed by further sensitisations to additional allergens including different allergen sources.
Re-exposure to these allergens causes an allergic reaction with local inflammation (redness and swelling,) common symptoms of which include: itching, sneezing, stuffy, runny nose etc. and in the most serious cases, a life-threatening reaction called anaphylaxis can occur.
Over time, the local allergen-driven inflammation (e.g., nose and lung) can lead to chronic persistent inflammation such as hay fever and asthma.