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

J ALLERGY CLIN IMMUNOL
VOLUME 120, NUMBER 3
Cox et al S61
have reported a significant relapse rate within 3 years of
discontinuing allergen immunotherapy.
One prospective controlled study was designed to study
the immunotherapy relapse rate during the 3-year period
after discontinuation of immunotherapy in 40 asthmatic
patients who had been treated with immunotherapy with a
standardized dust mite (D pteronyssinus) extract for 12 to
96 months. 14 Fifty-five percent of the patients relapsed.
The duration of efficacy was related to the reduction of
skin test reactivity at the end of immunotherapy treatment
(P 5 .003) and the duration of immunotherapy treatment.
The relapse rate was 62% in the group treated for less than
35 months compared with 48% in the group treated for
greater than 36 months (P 5 .04). Prolonged clinical
efficacy was demonstrated in a double-blind, placebocontrolled
study of patients with severe grass pollen–
induced allergic rhinitis who had been treated for 3 to 4
years with immunotherapy. 13 There was a switch to placebo
in half of the group (16 patients) after 3 to 4 years
of immunotherapy, and efficacy parameters were monitored
over the next 3 years. Seasonal symptom scores and
the use of rescue medication remained low for 3 to 4 years
after the discontinuation of immunotherapy, and there was
no significant difference between patients who continued
and those who discontinued immunotherapy. These studies
demonstrate the uncertainty of the long-term benefit of
inhalant immunotherapy after discontinuation.
Currently, there are inadequate diagnostic tools available
to identify which patients will experience a sustained
clinical remission after discontinuing inhalant immunotherapy,
and the duration of treatment should be determined
by the physician and patient after considering the
benefits and risks associated with discontinuing or continuing
inhalant immunotherapy.
A form to document indication for continuation of
immunotherapy can be found at http://www.aaaai.org or
http://www.jcaai.org.
Documentation and record keeping. Summary
Statement 56: The allergen immunotherapy extract contents,
informed consent for immunotherapy, and administration
of extracts should be carefully documented. D
An immunotherapy injection should not be given
unless adequate documentation is available in the patient’s
medical record. This also means that patients who receive
injections in a health care facility other than the office of
the prescribing physician must have appropriate documentation.
The recommended documentation for informed
consent allergy immunotherapy and prescription forms
can be found in the Appendix (Appendices 6-15), and
these include examples of immunotherapy prescription
and administration forms. These forms, along with examples
of immunotherapy consent and instruction forms, can
also be found at http://www.aaaai.org.
Injection techniques. Summary Statement 57: Allergen
immunotherapy extract injections should be given using a
1-mL syringe with a 26- to 27-gauge half-inch nonremovable
needle. C
Immunotherapy should be given with a 26- to 27-gauge
syringe with a half-inch nonremovable needle. Syringes
specifically designed for immunotherapy are available
from medical supply companies. Although recent
Occupational Safety and Health Administration guidelines
mandate the use of safety needles with allergy
injections, recent publications indicate a potential increase
in accidental needle sticks with the use of safety needles
compared with standard syringes. 289-291
If using shared specific patient vials (stock vials, such as
mixed vespid or dust mite mix), a single dose should be
drawn from each vial. Antigens from different vials should
not be combined in a single syringe. Furthermore, extra
care is needed to prevent using the wrong stock antigen.
Summary Statement 58: The injection should be given
subcutaneously in the posterior portion of the middle third
of the upper arm. D
Each immunotherapy injection should be given in the
posterior portion of the middle third of the upper arm at the
junction of the deltoid and triceps muscles. This location
tends to have a greater amount of subcutaneous tissue than
adjacent areas. The skin should be wiped with an alcohol
swab before giving the immunotherapy injection. This
does not sterilize the area, but it does remove gross
contamination from the skin surface.
Immunotherapy should be given subcutaneously.
Subcutaneous injections result in formation of a reservoir
of allergen immunotherapy extract that is slowly absorbed.
Absorption that is too rapid, such as after an
intramuscular injection, could lead to a systemic reaction.
The skin should be pinched and lifted off of the muscles to
avoid intramuscular or intravenous injection and to increase
access to the subcutaneous tissues.
The syringe should be aspirated to check for blood
return in the syringe before injecting. If blood is present,
the syringe should be removed and discarded in an
appropriate container (‘‘sharps’’ box). Another dose of
the allergen extract should be drawn into a new syringe
and a different site chosen for the injection. In theory,
removal of the syringe when blood is present reduces
the likelihood of intravenous administration, which could
lead to a systemic reaction. The syringe should be
appropriately discarded. A fresh syringe and needle are
necessary to determine whether a blood vessel has been
entered.
The plunger should be depressed at a rate that does not
result in wheal formation or excessive pain. Mild pressure
should then be applied to the injection site for about
1 minute immediately after removal of the needle. This
reduces the chance of leakage of the allergen extract,
which could result in a local reaction.
LOCATION OF ALLERGEN IMMUNOTHERAPY
ADMINISTRATION
Physician’s office
Summary Statement 59: The preferred location for
administration of allergen immunotherapy is in the office
of the physician who prepared the patient’s allergen
immunotherapy extract. D