Although medications available for allergy are usually effective, they do not cure allergies. Allergen immunotherapy is the closest thing we have for a "cure" for allergy, reducing the severity of symptoms and the need for medication for many allergy sufferers.
Allergen immunotherapy involves the regular administration of gradually increasing doses of allergen extracts over a period of years. Immunotherapy can be given to patients as an injection or as drops or tablets under the tongue (sublingual).
Allergen immunotherapy changes the way the immune system reacts to allergens, by switching off allergy. The end result is that you become immune to the allergens, so that you can tolerate them with fewer or no symptoms.