Immunotherapy Safety for the Primary Care ... - U.S. Coast Guard

Optimizing the Safety of Immunotherapy Administration Outside of the
Prescribing Allergist’s Office
I. Immunotherapy overview:
Definition: Allergen Immunotherapy is a treatment aimed at modifying the allergic
disease through a series of injections of a mixture of aeroallergen
extracts composed or clinically relevant allergens identified during the allergy evaluation
1. Immunotherapy has been shown to be effective in multiple controlled studies for
the treatment of allergic rhinitis, asthma and stinging insect venom hypersensitivity
2. Potential prophylactic treatment: may prevent the development of new allergies or
progression from allergic rhinitis to asthma
II. Immunotherapy potential mechanisms: Immunologic changes during
immunotherapy are complex. Successful immunotherapy is often associated with a shift
from TH2 to TH1 CD4 lymphocyte immune response to allergen. Immunotherapy
induces a number of immunologic changes. Studies over several seasons of
immunotherapy show that the usual seasonal rise of IgE is blunted by immunotherapy.
On the other hand, it is believed that IgG protective “blocking antibody” production is
stimulated by immunotherapy. However, these changes in IgE and IgG may not
correlate with clinical efficacy. Immunotherapy inhibits the early and late phase
responses, which results in decreased inflammation. Partial desensitization may play a
role in immunotherapy. Immunotherapy may also induce production of “regulatory” T
cells (CD4+CD25+) which may produce factors (IL-10and/or TGF-β) to down-regulate
allergic immune responses. Clinically effective immunotherapy may be the result of
some or all of these mechanisms.
III. Indications and Contraindication for Allergen Immunotherapy
1. Candidates: Patients with allergic rhinitis and/or asthma* with symptoms after
natural exposure to aeroallergens and demonstrable evidence of clinically relevant
specific IgE poor response to pharmacotherapy and/or allergen avoidance and 1 of
the following 1
a. Unacceptable adverse effects of medications
b. Desire to reduce or avoid long-term pharmacotherapy and the cost of
medication.
c. Coexisting allergic rhinitis and asthma
d. Immunotherapy may prevent the development of asthma in patients with
allergic rhinitis
e. Immunotherapy may prevent the development of new allergen sensitivities
2. Patients who are not allergen immunotherapy candidates: Medical conditions
that reduce the patient’s ability to survive a systemic reaction are relative
contraindications for allergen immunotherapy. 1