What is Immunotherapy?
By Dr. Bryan Wilcox
Allergic rhinitis or “hay fever” can adversely impact one’s quality of life. Allergic rhinitis causes a constellation of miserable symptoms such as nasal congestion, sneezing, watery nasal drainage, post-nasal drip, itchy nose, and often is associated with allergic conjunctivitis, which causes itchy, watery eyes.
In some patients, this process leads to further conditions such as nasal polyps or chronic sinus infections. Additionally, approximately 30 percent of allergy sufferers have asthma, which can be exacerbated by uncontrolled allergic rhinitis.
Three modes of therapy are available to treat allergic rhinitis: avoidance, medications, and immunotherapy. Medications include steroid nasal sprays such as Flonase or Nasonex, anti-histamines such as Zyrtec or Allegra, anti-leukotrienes such as Singulair, and anti-histamine nasal sprays such as Astelin. While effective for many allergy sufferers, medications only treat the symptoms of allergy once the reaction has occurred. Immunotherapy is the most effective therapy because it changes one’s immune system so the allergic reaction doesn’t happen in the first place.
Immunotherapy is a treatment in which small, regular doses of allergens are given to a patient, causing a down regulation of the immune system’s reaction to the allergens, thereby preventing the allergy response from occurring. This is sometimes referred to as desensitization. Most people know immunotherapy as allergy shots, in which small doses of offending allergens are injected under the skin, generally on a weekly basis. There is also a new form of immunotherapy administration known as sublingual immunotherapy, or SLIT, in which daily doses of allergens are dropped under the tongue by the patient at home.
Allergy shots have long been and continue to be the “gold standard” in immunotherapy. The shots are composed of a variable number of allergens tailored to the positive allergy tests of each individual. Typically, allergy shots are administered in the doctor’s office every week for a period of 3 to 5 years and are then discontinued. The symptom relief from allergy shots generally lasts another 3 to 5 years after stopping the shots, but then the beneficial changes in the immune system revert back and symptoms again increase. Allergy shots are generally very safe but do carry a very small risk of anaphylaxis, in which the allergic response is triggered causing swelling of the airway. This risk is exceptionally small when using the administration protocols currently used by most allergists, but is the reason why they are given at the doctor’s office.
Sublingual immunotherapy, or SLIT, is an alternative method of administering immunotherapy and is generating a lot of interest because the risk of anaphylaxis is almost zero and the convenience of taking the therapy at home is very attractive. SLIT is currently not FDA approved for the treatment of allergic rhinitis, but its off-label use has been occurring for decades in Europe and by many allergists in the U.S. The American Academy of Otolaryngic Allergy, or AAOA, has established a protocol for its members to follow who desire to offer this type of immunotherapy to their patients. SLIT is administered by placing several drops of allergen under the tongue with a medicine dropper once daily. SLIT has little to no risk of anaphylaxis, and there has never been a reported death from anaphylaxis due to SLIT therapy. Opponents of SLIT think that this may be because SLIT is less effective than allergy shots. However, many studies have proven SLIT to be an effective form of immunotherapy, several showing equal efficacy to allergy shots.
Considering the full array of treatments for allergies, there are few reasons why you should have to “put up with” your allergies. An ENT physician can diagnose and treat allergic rhinitis as well perform surgery for chronic sinusitis or nasal polyps, which might result from untreated allergies. So get treated and enjoy your nose again.