An allergen is the name given to a substance which can cause an allergy. Thousands of allergens range from pollen to egg proteins.
Most allergens contain proteins, but there are some, such as penicillin and other medications, which combine with proteins when they enter the body.
Some people are allergic to certain substances, while others may be unscathed by the same products. Allergies today may be sparked off by a wide range of diverse indoor or outdoor triggers or allergens, which have multiplied over the years.
