Allergy desensitization

Hyposensitization (or allergy desensitization) is a form of immunotherapy where the patient is gradually vaccinated against progressively larger doses of the allergen in question. This can either reduce the severity or eliminate hypersensitivity altogether. It relies on the progressive skewing of IgG ("the blocking antibody") production, as opposed to the excessive IgE production seen in hypersensitivity type I cases.
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Stimulation of the immune system with gradually increasing doses of the substances to which a person is allergic, the aim being to modify or stop the allergy "war" (by reducing the strength of the IgE and its effect on the mast cells). This form of treatment is very effective for allergies to pollen, mites, cats, and especially stinging insects (eg, bees, hornets, yellowjackets, wasps, velvet ants, fire ants). Allergy immunotherapy usually takes 6 months to a year to become effective and injections ("shots") are usually required for 3-5 years.