Allergy shots decrease sensitivity to allergy-causing substances so that exposure to the offending allergens (pollen, dust, molds, etc) will result in fewer symptoms. This does not mean that allergy shots are a substitute for avoidance of known allergens which is the treatment of choice, when possible.
Gradually increasing the amount and strength of allergen in the shots suppresses production of the allergy antibody referred to as IgE. Allergy shots increase the production of the allergy blocking or protective antibody (IgG). These changes may permit you to tolerate exposure to specific allergens with fewer symptoms as allergy shots are given in order to “immunize” you against the allergens causing allergic symptoms. How well the immunization process works varies with the individual and the amount of relief you will get is somewhat unpredictable. However, in properly selected patients allergy shots are the most effective and preferred method of treatment. The exact mechanisms of how the shots work is not completely understood but most likely changes the responses of immunity cells called Th1 and Th2 cells. Regardless it is proven that they do work and reduce allergy symptoms.
To qualify for allergy shots, you must be allergic to substances in the environment that you cannot avoid. Allergy shots should generally not be given for avoidable allergens.
However we do use shots to help decrease symptoms from pets: Cats, Dogs, and Horses with good success. We like to keep your pet but lose your allergy to them. They are often a family member that we simply cannot do without!
Diagnosis of allergy either can be in the form of a positive blood test (RAST/ELISA). In addition to demonstrable allergy by one of the above tests, symptoms such as hayfever, urticaria, or asthma should occur on exposure to the suspected allergens.
Improvement should not be expected immediately. It usually requires 4-6 months(sooner with RUSH build-up) before relief of allergy symptoms is noticed and it may take 24 months for the full benefits to occur. About 80% of allergic individuals on immunotherapy get significant improvement of their symptoms. This means that symptoms are reduced but do not necessarily go away completely. The patients who follow their treatment plan faithfully, avoid allergy triggers, and use medications properly have the best results approaching 90%.
The most common failures occur in patients who have work or school-related exposures to allergens, tobacco or wood smoke, or are smokers.
For many patients it is the best long-term treatment and the most cost-effective.
Allergy injections are usually begun at a very low dose. This dose is gradually increased on a regular (usually weekly) basis until a therapeutic dose (often called the “maintenance dose”) is reached. The “maintenance dose” often differs from person to person. Shots are usually given once or twice per week while the allergen dose is being increased. This frequency reduces the chances of a reaction and permits the maintenance dose to be reached In a reasonable amount of time. After the maintenance dose has been reached, injections can usually be given once a week for up to 18-24 months or occasionally longer. The goal is to spread allergy shots out to every 4 weeks over a period of several years.
Duration of Treatment
It usually takes 4-6 months to reach a “maintenance dose” by the conventional method but will be longer if there are adverse reactions to any of the allergy shots. The time also will be prolonged if allergy injections are not received on a regular basis. For this reason, it is important that the recommended schedule be follows. We offer an alternative to “conventional” build-up called RUSH or Rapid Desensitization in which you can achieve a “maintenance dose” in ½ day. The rapid procedure is offered to patients that medically qualify and are willing to take our prescribed medications a few days prior to and during the procedure.
Allergy shots should not be started if you anticipate you cannot get them regularly. The practice reserves the right to discontinue shots if a patient frequently misses shots or fails to follow the schedule intervals or doses.
The length of time injections are given depends on the response to treatment. Ideally, you should experience relatively few symptoms without requiring much medicine for at least 1 year before the shots are stopped. A typical duration of treatment is 3-5 years. There are instances when treatment may be continued beyond this time. Since the duration of and changes in immunotherapy must be individually tailored, regular follow-up clinic visits are essential. Make a follow-up appointment when you reach maintenance level of your build-up. Additionally, an appointment should be scheduled if repeated reactions occur during your build-up phase. At follow-up appointments, adjustment and interval changes are made that are important to your treatment and are cost effective. Missing appointments can delay the reduction of intervals and save money by medication and shot reductions.
Allergy shots are associated with widely recognized risks. This is because you are being injected with a substance to which you are allergic. Most reactions occur within 15 minutes; however, a reaction may occur hours later. Reactions are graded as follows.
0 No significant reacton, or small area of redness up to the size of a half dollar without swelling.
1 Redness greater than the size of a half dollar and/or swelling or wheal or hive formation. This
is common and usually not significant.
2 Delayed local reactions that occur hours a day after a shot are not dangerous but may be
uncomfortable requiring shot adjustments.
3 Cutaneous (skin) only
May consist of a rash, such as hives, away from the shot site./ This is uncommon and while not
dangerous, its presence does suggest that more serious reactions may occur in the future if
caution is not exercised.
4 Generalized pruitus (itching) and/or sneezing
May consist of increased allergy symptoms such as nasal congestion, sneezing or itchiness
especially in the mouth or throat.
Consists of wheezing, coughing, shortness of breath, or chest tightness. While this occurs
infrequently, it is of major significance if not treated immediately
6 Anaphylaxis (happens less than 1 in a million allergy shots given)
A sensation of not feeling “right” is a frequent prelude. Symptoms may include hypotension
(low blood pressure), laryngeal edema (swelling of throat), severe wheezing, lightheadedness
and a fainting or flushed feeling (which may precede shock), nausea and vomiting, increased
allergy symptoms, itchy skin (which would accompany hives), hacking cough, severe headaches
and abdominal discomfort.
While a rare occurrence, anaphylaxis is serious and potentially life-threatening. Without
treatment, the person could die or be severely damaged (brain, kidney, heart).
If one of the more significant reaction occurs, the dose of extract given will be reduced and cautiously increased again if there are no further reactions.
In general, 20% of people who receive allergy shots will have a systemic reaction at some point during their course of therapy. This means that there is a 1 in 5 chance that you will experience a systemic reaction. Since a large number of injections are given during a 5-year course of therapy, no single shot is likely to cause a reaction. It is estimated that there are 5 allergy shot-related deaths per year in the United States. While most systemic reactions are not life-threatening, if treated promptly, this fact does stress the importance of being in good health on those days when shots are given and remaining in the clinic for observation. Reduced lung function is associated with increased risk of systemic reactions. To identify times when you may be at risk, peak flows can be measured before and after each injection. Before the shot, it is your responsibility to notify a staff person that you are having problems.
Any medical facility that givens allergy injections should be equipped to treat any reactions that may occur. Before your shot, you should check with the facility to be certain that this is the case. It is your responsibility to notify a staff person that you are having problems.
Alternatives to Immunotherapy
Immunotherapy is not always necessary. Alternatives to receiving immunotherapy include:
* avoidance of your allergic triggers, if possible.
* use of medications to control allergy symptoms.
* anti-IgE (Xolair) therapy for moderate-to-severe asthma.
Currently, patients with stinging insect allergies have no safe effective alternative to allergy shots.
Subligual tablets are now approved for grass and ragweed and are called SLIT.
The Hickory Allergy and Asthma Clinic charges a fee for the bottles of allergy extract. In addition, there is a clinic fee each time an injection is given at the Hickory Allergy and Asthma Clinic. Ask the front desk staff for the exact charges.
In the event of an allergy shot reaction at Hickory Allergy and Asthma Clinic, you are responsible for any additional fees that are associated with treatment of the reaction. in addition, if admission to the hospital is necessary for observation after a severe systemic reaction, you are responsible for fees associated with the admission. Although rare, reactions do happen. Expect that you will have some reactions. We will work with you closely to help avoid future reactions.
Specific Instructions for Patients Receiving Immunotherapy
1 In general, injections should be given at a health care facility. Allergy shots should never be given at home without special training and precautions taken by family members. Patients and their family members should realize the risks involved and are held responsible for the safe administration of the shots and emergency treatment, if necessary. Giving shots at home is a privilege granted after training and appropriate medications are available to the family,
2 Remain in the medical facility for the minimum of 15 minutes after each injection in case you should experience an immediate allergic reaction. Each time you come in for allergy shots, check with the allergy shot person or staff before you leave.
3 Before allergy shots are given, report any current illness, any new medications you are taking or any delayed reaction to the allergy shot which you noticed after you left the medical facility where the shot was given.Discuss any problem with staff/personnel regarding your last shot before your next shot.
4 Keep your scheduled follow-up clinic appointments. ou should be seen in the Hickory Allergy and Asthma Clinic at about 4 months after starting shots and then, at least, every 12 months once you reach your maintenance dose or there may be a refusal to refill the allergy shot extract.
5 New vials should be ordered 2 weeks in advance of needing them. Reduce the first injection out of a new bottle to half of the maintenance dose ant then, subsequently, follow the schedule to maintenance level. Doses in a new supply are reduced as there may be differences in the allergen content of these new vials (fresh vials are stronger) and, therefore, an increased risk of an allergic reaction to the shot. If you are on shots every 2-3-4 weeks or monthly, you need to follow the written instruction back to your maintenance level. Then spread the allergy shots out to 2-3-4 weeks intervals.. After reaching maintenance, you will receive sufficient extract to last about 6 months and will only need to reorder about twice per year.