Allergies are an abnormal response of the immune system to a substance known as an allergen. Allergens are substances to which particular individuals have extreme sensitivity. When a person is exposed to an allergen, the body releases chemicals including histamine, which produce an allergic reaction.
Immunotherapy is the administration of small doses of the allergen causing the problem which is gradually increased to help the patient develop increased tolerance. Immunotherapy works to bolster the immune system without triggering an allergic reaction. Some of the most common allergens are pollen, dust mites, mold, and animal dander.
Candidates For Immunotherapy
Immunotherapy is a good option for patients who have persistent allergies for more than three months of the year, do not respond well to allergy medications, or are in danger because of their allergy. Immunotherapy can relieve allergy symptoms and help reduce the frequency of reactions.
Subcutaneous Immunotherapy – SCIT
A course of immunotherapy typically begins with the injection of minute quantities of the allergen injected into the patient’s arm once a week. Gradually, these doses are increased. In a month or two, the patient is usually receiving the optimal amount of allergen in the injection, enough to demonstrate sufficient tolerance to allow the patient limited exposure to the allergen without developing symptoms. This is referred to as a maintenance dose.
Once the maintenance dose is reached, the patient will receive the same dose with decreasing frequency. That same dose may be administered every 2 weeks for about 6 months. At that time, the period between injections is increased to about 4 weeks. Patients may be kept on a maintenance dose once a month for up to 5 years to help them retain at least partial immunity to the irritating allergens.
In some instances, immunology for allergens may be administered more intensively, reaching the maintenance dose more quickly. This variety of treatment is called cluster, or rush, immunology.