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About sensitization
- Sensitization is a process in which the immune system develops a reaction to a substance that is normally harmless, such as food, pollen, or animals like cats and dogs.
- When the immune system encounters an allergen it considers harmful or foreign, it can produce antibodies against it and may react when exposed to the allergen again.
- Being sensitized does not necessarily mean that you will develop allergy symptoms. Some people have antibodies to an allergen without experiencing an allergic reaction.
- Sensitization can be investigated through blood tests that measure antibodies to specific allergens or through skin tests where the reaction to small amounts of an allergen is assessed.
- Allergy blood tests measure IgE antibodies, and higher levels can indicate a greater likelihood of allergy to a specific allergen. These tests can also be used as part of an allergy investigation and to monitor treatment.
What is sensitization?
Sensitization is a process where the immune system develops a reaction to a substance that is not normally harmful to the body, such as a food, pollen or an animal such as a cat or dog. When the immune system becomes sensitized to a substance, the person is often called "sensitized" to that substance.
The immune system produces antibodies
Sensitization occurs when the immune system is exposed to a substance, or allergen, that the body perceives as harmful or foreign. The immune system produces antibodies against the allergen, which can lead to allergic symptoms on the next exposure to the allergen. The more a person is exposed to the allergen, the more likely it is that the person will become sensitized to the substance.
Sensitization can be investigated by testing for antibodies against the allergen in the blood or by performing skin tests where small amounts of the allergen are applied to the skin and the reaction is measured. However, sensitization does not always have to lead to allergic symptoms. Many people can be sensitized to an allergen without developing allergic reactions when exposed to the substance.
Measurement of IgE levels – part of an allergy investigation
In a blood test for allergy testing, the amount of immunoglobulin E (IgE) antibodies in the blood is measured. Measuring IgE levels in the blood can indicate whether a person has an overreaction to a specific allergen. The higher the level of IgE in the blood, the greater the probability that the person is allergic to the specific allergen.
Allergy testing through blood tests can be used as part of the investigation of allergies and to monitor the effectiveness of allergy treatments.
