Asthma and allergies are two quite personal conditions in the sense that they can work so differently from one person to another. Treatment plans don't come in a one-size-fits-all formula. Lifestyle choices and/or demands can make it easier or more difficult to avoid allergens. Sometimes medications that once worked have become ineffective. When medications aren't helping and you're having a hard time avoiding your allergens, it might be time to consider allergen immunotherapy, or "allergy shots."
What is Immunotherapy?
With immunotherapy treatment, you receive increasingly higher doses of your allergens over time, gradually becoming less sensitive to them. Allergy shots have been proven effective for symptoms caused by grass, tree and weed pollens, dust mites, cat dander, certain molds and stinging insects.
To date, allergen immunotherapy is the only treatment that has the potential to provide long-term prevention of allergic asthma or rhinitis symptoms. Allergy shots may have a lasting effect after they are stopped, whereas medications do not.
Who is Eligible?
To help determine if you will be a good candidate for allergy shots, your physician will look at two key factors: how long you experience allergy symptoms each year and how well other treatments are controlling them. People with perennial or prolonged allergies are generally the best match, as well as those needing multiple medications for their symptoms. A switch to allergy shots is usually not cost-effective for patients whose seasons last only a few months and who are achieving good control with cromolyn sodium inhalers, topical corticosteroids or non-sedating antihistamines.
Additional considerations include your age and health. Patients into their 60s can be good candidates for treatment. However, the younger the patient, not only the better the chances for relief, but also the more years of potential benefit. Your body must also be able to respond to epinephrine, which would be used in the rare event that you should have a severe reaction from the injections. Arrhythmia or other heart problems would make you ineligible in this case.
How Does the Process Work?
Once your doctor has verified that immunotherapy is a good option for you, he or she will conduct tests that will determine what allergens should be in your allergy extract. Skin testing is one of the most common, accurate and inexpensive ways to do this.
In prick/scratch testing, a small drop of a possible allergen is placed on the skin, followed by lightly pricking or scratching through the drop with a needle. In intradermal (under the skin) testing, a very small amount of allergen is injected into the outer layer of skin. With either test, if you are allergic to the substance, you will develop redness, swelling and itching at the test site within 20 minutes. You may also see a raised, round area that looks like a hive. Usually, the larger the area, or wheal, the more sensitive you are to the allergen. Most people are tested for about five to 25 allergens at a time, depending on whether sensitivity is being tested for indoor allergens only, or for both indoor and outdoor allergens.
After allergen identification comes the actual treatment. You'll begin with shots once or twice a week, until you start to feel relief (this process usually takes four to six months). Monthly maintenance doses are then given to help keep your "allergen resistance level" steady. You can expect your symptoms to be reduced after your first year of immunotherapy. If not, the use of allergy shots for your condition should be reconsidered. After you've been taking allergy shots for three to five years, it's time to stop for a reevaluation of treatment and symptoms. If the result is a return of symptoms, another course of therapy may be recommended, as a gradual relapse has been known to occur in some patients.
A Quicker Alternative
Because of time, cost and convenience issues, rush immunotherapy has reemerged as a viable option to conventional allergy shots. First suggested 65 years ago by British physician John Freeman, this accelerated version of the traditional course of shots brings patients to maintenance dosing levels within several weeks instead of months.
A typical rush regimen at National Jewish Medical and Research Center schedules four daily injections at one-hour intervals on five consecutive days. Maintenance doses are reached in five to 10 days. After maintenance is achieved, injections move to a weekly, then biweekly, and finally, a monthly schedule.
In one recent study, 44 patients, ages 2 to 50, successfully achieved full maintenance dosing in one day. Diagnosed with a variety of conditions including asthma, allergic rhinoconjunctivitis and chronic sinusitis, all were able to complete the therapy and showed no signs of blood pressure changes. Peak flow meter readings also remained stable. Participants had been pre-medicated with prednisone and various antihistamines for two days prior to the study as well as on the morning it began. Two patients developed and were treated for generalized itching.
SOURCE: This information should not substitute for seeking responsible, professional medical care. First created 1995; fully updated 1998; most recently updated 2005.
© Asthma and Allergy Foundation of America (AAFA) Editorial Board