Just The FAQS: On Allergy Shots

Allergy shots may reduce need for medication

Frequently Asked Questions (FAQs) About Allergy Shots

Patients evaluated in my office go through three phases of examination, followed by a treatment plan. The phases of examination include:

1) A detailed history about their symptoms, level of severity, pattern (seasonal or year round…) other medical problems, environmental triggers (indoor and outdoor, school or work related), family history and medication experience.

2) A physical examination is done.

3) Skin testing and possibly Pulmonary Function Testing is done.

Treatment involves four tiers:

1) There is emphasis on the avoidance of trigger factors (established by skin testing) by implementing environmental controls.

2) Medications are selected to address specific symptoms and control inflammation

3) We provide verbal, written and internet resources to learn more about the first two tiers.

4) We recommend allergy shots for children or adults that fail to respond adequately to medications and environmental controls.

Six FAQs (Frequently Asked Questions) about Allergy Shots (also termed Immunotherapy, Desensitization, Allergy Vaccination)

1) What are allergy shots?

Allergy shots are injections of extracts (materials obtained from specific allergy sources such as trees or grass or other triggers) that have measured amount of protein representing the triggers one has hypersensitivity to. Yes, you are being exposed to the very thing(s) you have been told to avoid in the environment, but in such small amounts, that it should not cause allergy symptoms. The injections, usually one or two, are given in the more fatty part of the upper arm, on a weekly basis (the first 9 to 12 months). The starting doses are over a 100,000 fold weaker than the doses given several months later. The injection doses are gradually increased in potency and amount injected over time. Exactly how allergy shots work is not completely clear but research has identified a number of possible mechanisms. The desired outcome is the establishment of tolerance to specific allergy triggers. This is successful 70-80% of the time.

2) Who should get allergy shots?

Allergy shots are recommended:

- For people that fail to have an adequate response to medications and environmental controls

- When side effects from medications limit the effectiveness of treatment.

- When allergy triggers are unavoidable (outdoor pollens and molds) and lead to moderate to severe symptoms

- When both upper and lower airway allergy symptoms are involved (hayfever and asthma)

- When there is a preference by the patient or family to maximize non-medicinal therapies for allergy control

3) How many years will I be on allergy shots?

If the allergy shots are helpful, they are generally given for five years. Some patients choose to stay on shot therapy longer because of the limited need for medications and overall effectiveness. We encourage our patients that have allergic rhinitis, and asthma to stay on shots more than five years, when the asthma (in addition to the rhinitis) has responded very well. Studies have shown that allergy shots may reduce asthma symptoms and allow for better control.

If the allergy shots are not helpful, they are stopped after 12 to 18 months.

4) Are allergy shots only for older children and adults?

No, children as young as 5 years old may be given allergy shots. Occasionally, a 3 or 4 year old may be started on shots because of the severity of their allergies and/or their intolerance to medications (side effects of medications may limit their use, especially in young children).

We have started patients older than 60 years of age on allergy shots.

5) How safe are allergy shots?

Allergy shots have been given for almost 100 years and have gone through several decades of modifications, based on research. Several years ago people were on shots for thirty or more years. At the time, it was thought that people needed them life long. Reports failed to show problems associated with allergy shots, on a cumulative (build up over time) basis.

Now, any time a shot or shots are given, one is at risk of having a local and/or systemic reaction. Local reactions if they occur are at the site of the injection. They may be small (less than a dime size) or large (several inches in diameter). Redness and swelling, associated with itching and mild burning may be experienced. Treatment includes elevating the arm, applying ice or cold compress, and taking Benadryl (beware of sedation and fatigue with Benadryl).

Systemic reactions are potentially more severe. They are characterized by symptoms, rash or swelling occurring away from the injection site. One may have hives, lip, throat or tongue swelling, difficulty breathing or lightheadedness, although this is very rare. These symptoms, collectively represent an anaphylactic reaction. Such reactions may be fatal if untreated.

Steps are taken, in our office to prevent severe reactions to allergy shots. Some important ones are:

1) Always wait 20-30 mins after allergy shots are given

2) Report to your allergist or nurse, any symptoms or signs of ill feelings associated with a previous allergy shot

3) Come back to the office if any of the above signs of a systemic reaction occur after leaving the office if close by. Otherwise go directly to the nearest emergency department or urgent care, or call 911.

4) If you have a fever, respiratory infection or other illness that is moderate to severe, skip your shots that day or week.

5) Inform the nurse about any new medications and be aware of the class of medications usually avoided when on allergy shots (beta blockers such as Lopressor and Propranolol).

6) Try to avoid rigorous exercising within 2 hours of getting your allergy shot

6) What happens if I become pregnant while on allergy shots?

We continue giving allergy shots during pregnancy unless the obstetrician is against it (which is rare). Allergy shots have been safely given during pregnancy, for years. No increased risk of birth defects has been reported. We actually feel that by controlling allergy problems during pregnancy, mom sleeps better, feels better and has lower risk of requiring more allergy drugs or antibiotics for upper respiratory infections (which often complicate active allergic rhinitis.

We do not start women on allergy shots if they are pregnant, or are trying to get pregnant. Since early on, we are giving increasing doses of extract, there is a higher risk (although small) of having a systemic reaction and therefore requiring a shot of Epinephrine to treat the reaction. The Epinephrine may cause preterm labor (possible early delivery).

If a patient finds out she is pregnant within the first few months of starting shots, we will usually stop them. If she is at or near maintenance doses they will be continued throughout the pregnancy at the same dose (decreasing the likelihood of having a systemic reaction).

Allergy shots represent the most readily available treatment that may be disease modifying (this means have a beneficial impact that lasts long after being stopped) for patients with allergic rhinitis and asthma. On occasion, I have to spend several minutes convincing patients (and parents) that it is time to stop shots. People appreciate feeling more normal, being able to breathe and having less need for medications.

Do you have other questions about allergy shots?

If so, email me at: www.AllergyQA@aol.com

Future topics: Eczema (Atopic Dermatitis) and the best ways to moisturize dry skin

Herbals: “Beware if you have allergy problems”

Hives (Urticaria) and Swelling (Angioedema)

Above illustration from: Atlas of Allergic Diseases, Phillip Lieberman and Michael Blaiss