In its early stages, allergy can appear as a seemingly benign condition, such as hay fever during the pollen season. Some people gradually build up an allergic condition over several years before experiencing any symptoms. Others experience sudden, life-threatening anaphylactic reaction following ingestion of a certain food, drug, or an insect bite. Additionally, some allergies that start as eczema or gastrointestinal problems can evolve into asthma, frequently involving respiratory symptoms such as hyper reactivity and obstruction of the airways.
Allergy undergoes dynamic changes over time, and the term "Allergy March" is often used to describe this characteristic disease progression. During a typical Allergy March sequence, sensitization and visible symptoms generally:
- appear during specific age intervals
- persist over a number of years
- tend to spontaneously decrease with age
As allergy is constantly evolving, an ImmunoCAP blood test taken at one specific time will only show the disease status at that particular moment. Only regular testing of specific allergens at given intervals of time will provide the information needed to accurately follow disease development.