Antihistamines. As the name indicates, an antihistamine counters the effects of histamine, which is released by the mast cells in the body's tissues and contributes to allergy symptoms. For many years, antihistamines have proven useful in relieving sneezing and itching in the nose, throat, and eyes, and in reducing nasal swelling and drainage.
Many people who take antihistamines experience some distressing side effects: drowsiness and loss of alertness and coordination. In children, such reactions can be misinterpreted as behavior problems. During the last few years, however, antihistamines that cause fewer of these side effects have become available by prescription. These non-sedating antihistamines are as effective as other antihistamines in preventing histamine-induced symptoms, but do so without causing sleepiness. Some of these non-sedating antihistamines, however, can have serious side effects, particularly if they are taken with certain other drugs. A patient should always let the doctor know what other medications he/she is taking.
Topical nasal steroids. This medication should not be confused with anabolic steroids, which are sometimes used by athletes to enlarge muscle mass and can have serious side effects. Topical nasal steroids are anti-inflammatory drugs that stop the allergic reaction. In addition to other beneficial actions, they reduce the number of mast cells in the nose and reduce mucus secretion and nasal swelling. The combination of antihistamines and nasal steroids is a very effective way to treat allergic rhinitis, especially in people with moderate or severe allergic rhinitis. Although topical nasal steroids can have side effects, they are safe when used at recommended doses. Some of the newer agents are even safer than older ones.
Cromolyn sodium. Cromolyn sodium for allergic rhinitis is a nasal spray that in some people helps to prevent allergic reactions from starting. When administered as a nasal spray, it can safely inhibit the release of chemicals like histamine from the mast cell. It has few side effects when used as directed, and significantly helps some patients with allergies.
Decongestants. Sometimes re-establishing drainage of the nasal passages will help to relieve symptoms such as congestion, swelling, excess secretions, and discomfort in the sinus areas that can be caused by nasal allergies. (These sinus areas are hollow air spaces located within the bones of the skull surrounding the nose.) The doctor may recommend using oral or nasal decongestants to reduce congestion along with an antihistamine to control allerigic symptoms. Over-the-counter and prescription decongestant nose drops and sprays, however, should not be used for more than a few days. When used for longer periods, these drugs can lead to even more congestion and swelling of the nasal passages.
Immunotherapy, or a series of allergy shots, is the only available treatment that has a chance of reducing the allergy symptoms over a longer period of time. Patients receive subcutaneous (under the skin) injections of increasing concentrations of the allergen(s) to which they are sensitive. These injections reduce the amount of IgE antibodies in the blood and cause the body to make a protective antibody called IgG. Many patients with allergic rhinitis will have a significant reduction in their hay fever symptoms and in their need for medication within 12 months of starting immunotherapy. Patients who benefit from immunotherapy may continue it for three years and then consider stopping. Although many patients are able to stop the injections with good, long-term results, some do get worse after immunotherapy is stopped. As better allergens for immunotherapy are produced, this technique will become an even more effective treatment.