Desensitization therapy, or immunotherapy, refers to the process of making allergens more tolerable by having them formulated into various extracts of varying concentrations, which are given to allergic patients by subcutaneous injections, sublingual administration, and so on. Desensitization is mainly done by making allergens such as dust mites, pollen, and animal dander into intravenous fluids or oral medications to cause a particularly mild allergic reaction that is barely noticeable to the patient. The concentration should be from low to high, and the dose should be gradually increased from small to large, so that the patient can be prompted to increase the tolerance to the allergens, and gradually adjust the patient’s immune mechanism, so as to achieve the reduction or control of allergic symptoms of a therapeutic method. This treatment must be used under the strict guidance of a doctor, and during the course of the treatment, the patient needs to be reviewed regularly, and should always monitor his or her own status, and should not increase or decrease the dosage of the drug arbitrarily.