What Is Oral Immunotherapy?

Immunotherapy involves the introduction of small amounts of the allergy-causing substances, known as an antigen, into the patient's body. Over time, as the concentration is gradually increased, the patient develops a normal tolerance to the antigen. Many people are familiar with injection immunotherapy, in which a physician injects the antigen into the patient’s arm. Typically, patients receive one shot weekly or monthly over a period of three to five years. Oral immunotherapy works similar to the injection method. The difference is, patients take the antigen orally. This type of therapy is also called “sublingual” because antigen drops are placed under the tongue then swallowed. Because of the lack of systemic life-threatening reactions, they can be self administered at home. When given the choice, many patients choose oral therapy because it usually requires fewer clinic visits, and it costs less than injection therapy.