Patients can get caught in a vicious circle of use, relapse, and more use. The only solution is to stop using the drug altogether. The corticosteroids, hormone-like drugs that suppress the immune response, may also be useful in relieving allergy symptoms. They are usually administered as sprays, but are sometimes taken by mouth. While long-term use of oral corticosteroids can depress the activity of the adrenal glands, resulting in diminished resistance to infection, and cause other serious side effects, the nasal preparations used to treat allergic rhinitis are not thought to have any effect on the body as a whole.
Corticosteroids are available only by prescription.
First employed in the 1920s, immunotherapy consists of injecting gradually larger amounts of the allergens that cause the patient's allergic response. At the beginning of the treatment the dose is intentionally much too small to cause a reaction. The dose is gradually increased to a level that protects the patient from whatever is causing the allergy. It usually takes six to 12 months to reach a protective dose. Whether or not the patients can successfully stop receiving allergy shots is uncertain.