Sensitization – it an alteration of responsiveness of the body to the presence of foreign substances. In the development of the allergy an individual becomes sensitized to a particular allergen and reaches the state of hypersensitivity.
The phenomena of sensitization are due to the production of antibodies.
Desensitization – it is also known as hyposensitization. It is a method for reducing the effects of a known allergen by injecting, over a period, gradually increasing doses of the allergen until resistance is built up.