Allergen Immunotherapy (Allergy Shots)

Currently, There are two methods of delivery; subcutaneous (SCIT) and sublingual(SLIT) Currently in the United States, SCIT is a predominant form of delivery, but in Europe, SLIT is overtaking SCLIT as the major modality of treatment. Dr. Song has added the SLIT approach to the conventional SCIT in 2011.

Subcutaneous Immunotheraopy (SCIT)(shots)

Indications

• High allergen sensitivity
• Symptoms not controlled by other therapeutic means
• Desire to “cure” the disease
• Prevention of allergic diseases

Efficacy

• Effective for hay fever(allergic rhinitis) and asthma.
• Most effective for people with bee sting allergy: over 90 % success rate.
• More effective in early stage of the disease.
• More effective for people who have fewer allergies.

Adverse Effect

• About half of the patients experience some injection site swelling.
• Mild systemic reaction such as sneezing and rash affect ~10% of the patients.
• Severe reaction such as shock is reported in 1/10,000 patients.
• Most of these adverse effects can be immediately treated.

Injection Schedule

• Initially once or twice a week.
• The doses are increased gradually to a maintenance level over 3 – 6 month period
• Once the maintenance dose is achieved, the injection interval is increased gradually to 4 weeks.

Injection protocol

• Patients are observed in the office for a minimum of 20 minutes after receiving the injection so that adverse reactions can be treated.
• Patients are required to take an antihistamine before coming to an allergy shot appointment.

Sublingual Immunotherapy (SLIT)

Allergen drops are applied under the tongue instead of being given by injection.

How does it work?

The studies show that the sublingual area is one of the most ideal sites for effecting the beneficial change in our immune systems (1).  In this area, the allergens are taken up and retained by the special cells for up to 48 hrs.  The interaction between allergens and the special cells initially induce the tolerance and eventually (after several months)  permanent decrease or abrogation of allergic response.

Who can benefit from it?

Children and adults with allergic rhinitis and asthma, and possibly with atopic dermatitis, latex allergy, and food allergies (2).

How effective is it?

There are more than 60  randomized, double-blind, placebo-controlled trials with SLIT (2). Most studies demonstrated efficacy for allergic rhinitis and asthma.   Both, the Cochran review (accepted way of gauging efficacy) and meta-analyses, have demonstrated that SLIT  is effective way of treating allergic rhinitis, asthma, and dermatitis.  

How does it compare to SCIT?

• Equally efficacious
• Fewer side effects.
• Can be used for young children
• May be used for food allergies, latex allergy, poison ivy/oak
• More convenient, Less time consuming
• Economical
  

Evidence-based treatment scores of I & II are considered excellent to good. Passalacqua et al, JACI 2007:119(4) 881-891

Is it approved by FDA?

Although used quite commonly in Europe, it is not yet approved in the United States. Clinical trials are still going on.

Is it being used in USA?

Many ENT and allergist have been using it off-label.  Used by early allergists in ~1900 and popularized in 1945 for a short time.  Then the practice of SLIT has re-emerged for the last several years.

How to get started?

Depending on the results of the allergy skin test, Dr.Song will prepare the allergen mix. 
Initially, the allergen concentration may be low and be increased later.
The patient will be supervised for his first SLIT  administration in the office.

How to follow up. 

A patient needs to see Dr. Song monthly for the first 3 months and then every 3 months thereafter. 

How long?

Most studies indicate that one needs to be on it for 4-5 years for the permanent benefit.

What is the cost?

Currently, the insurance companies do not pay the expense since it is an off-label treatment. The cost is approximately $ 50-100 / month depending on the number of allergens included in the preparation.

Reference:

1. Frall, Mucosal immunization approach to allergic diseases. Allergy and Asthma Proceedings, Jan-Feb 2007 Vol 28
2. Passlacuq, et al, WAO J,  July 2010, p216

Instruction for New Immunotherapy (Allergy Shot) Patients

Information For New Patients Starting Immunotherapy

1. From your skin test results, we have prepared allergen sets. They have been diluted to a very weak concentration. Each time you come in we will increase your dose, thereby increasing your tolerance to those things you are allergic to. Therefore, it is important for you to come in on a regular schedule. For the first 2-3 months, you will need to come in twice a week. Then the injection frequency will decrease to once a week, every 2 weeks, every 3 weeks, and eventually every 4 weeks.
2. Studies have shown that allergen injection therapy if administered properly, is successful in relieving symptoms in the majority of patients with allergic rhinitis and allergic asthma. The rate and degree of improvement vary with individual patients. For these reasons, you will require visits to the doctor every 3 months to monitor your progress. We will inform you when to schedule these visits.
3. Local reactions are the reactions occurring at the injection site. Systemic reactions refer to any symptoms (shortness of breath, generalized itchiness, feeling dizzy etc) occurring away from the site of injection. Systemic reactions are rare, but if they occur, they would do so during the first 20 –30 minutes. Therefore, it is mandatory to wait 20 minutes in the office so that we can treat you. To minimize the risk of reactions, you are requested to take an antihistamine such as Allegra or Claritin 1 – 2 hours before your appointment. Please show the nurse your arms before leaving the office so that we can record the extent of your local reaction.
4. If you have a systemic reaction outside of our practice, please contact our office immediately by phone. If you are in the vicinity, return promptly to our office. In the event that you cannot reach our office, report to the nearest emergency room.
5. When starting your injections, your first shot may be a skin test (intradermal) to make sure the concentration is not too strong. The doctor must be in the office during your first injection.
6. Check your injection sites 4 hours later. If there is an area of redness, swelling or both 1-inch diameter or larger, it is important for you to report it to us on your next visit.
7. No shots can be given if you are running a fever of over 99 degrees, are having an increased asthma symptoms, or you are having an acute allergic episode.
8. Check with us to see if your current medicines are safe during immunotherapy. If you are pregnant or planning pregnancy, please let us know.
9. It is important that you do not engage in any strenuous physical activity for 90 minutes before and after injections.