How does Immunotherapy (Allergy Shots) Work?
Immunotherapy is a process in which an allergic patient can become desensitized to those pollens and inhalants that trigger allergic rhinitis (nasal congestion), allergic conjunctivitis, asthma and insect reactions. Small doses of the actual allergic substance are injected weekly. Each week the dose is increased. Gradually a protective antibody, also known as Immunoglobulin G, is formed to block the allergic reaction. When someone has allergy, they have high levels of the allergic antibody, Immunoglobulin E (IgE), in their blood. This IgE is activated by the allergen (dust mites, ragweed, cat, etc), and it attaches itself to “mast” cells that release histamine. The histamine causes a release of a fluid that causes swelling and congestion. It can cause a tightening of the airways to create asthma.
The change induced by immunotherapy is gradual. Many patients notice an improvement within six (6) months at which time the patient should schedule a 6-month evaluation appointment. Progress is evaluated every six (6) months to one (1) year. Immunotherapy does not work in about 5% of patients who were correctly diagnosed to have significant allergies.