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

S56 Cox et al
J ALLERGY CLIN IMMUNOL
SEPTEMBER 2007
TABLE XI. Procedure for dilutions from the maintenance concentrate (which is termed 1:1 vol/vol)
Dilution from maintenance
concentrate vaccine Volume Volume (mL) Diluent volume (mL) Final volume
1:1 (vol/vol) 1.0 0.0 1.0 1:1 (vol/vol)
1:1 (vol/vol) 2.0 8.0 10.0 1:5 (vol/vol)
1:1 (vol/vol) 1.0 9.0 10.0 1:10 (vol/vol)
1:10 (vol/vol) 1.0 9.0 10.0 1:100 (vol/vol)
1:100 (vol/vol) 1.0 9.0 10.0 1:1000 (vol/vol)
All dilutions are expressed as vol/vol from the maintenance concentrate.
If the appropriate concentration of each allergen extract is
added, then adding additional allergens to the maintenance
concentration will have no effect on the concentration of
the other allergens, as long as the additional allergens are
replacing diluent. For example, if the desired maintenance
concentration for cat is 2000 BAU/mL, 2 mL of the
manufacturer’s extract (cat, 10,000 BAU/mL) can be
added to 8 mL of diluent or 8 mL of other allergens, and
the final concentration of cat will be 2000 BAU/mL in
both mixtures. Once the diluent is all replaced, addition of
further allergens will result in undesirable dilution of all
allergens in the maintenance mixture.
Dilutions of the maintenance concentrate
Summary Statement 39: Serial dilutions of the maintenance
concentrate should be made in preparation for the
build-up phase of immunotherapy. D
In preparation for the build-up phase of immunotherapy,
serial dilutions should be produced from each maintenance
concentrate. Typically, these are 10-fold dilutions,
although other dilutions occasionally are used. These
dilutions should be labeled in terms of vol/vol to indicate
that they are dilutions derived from the maintenance
concentrate. For example, serial 10-fold dilutions from
the maintenance concentrate would be labeled as 1:10
(vol/vol) or 1:100 (vol/vol). Alternatively, the vial dilutions
can be labeled in actual units (eg, 1000 BAU or 100
BAU), but this system can be complicated if allergens with
different potency units are used (eg, wt/vol, BAU, AU, or
PNU) and make it difficult to easily interpret the vial label.
Instructions on how to prepare various allergen extracts
dilutions are shown in Table XI. If the final volume of the
diluted allergen immunotherapy extract to be produced is
10 mL, then one tenth of that final volume, or 1.0 mL,
should be removed from the more concentrated allergen
immunotherapy extract and added to a new bottle containing
9.0 mL of diluent.
Labeling dilutions
Summary Statement 40: A consistent uniform labeling
system for dilutions from the maintenance concentrate
might reduce errors in administration and therefore is
recommended. D
During the build-up phase of immunotherapy, a number
of dilutions of the patient’s maintenance concentrate are
needed. Use of one labeling system to indicate dilutions
might help to avoid administration errors (Table XII). In
TABLE XII. Suggested nomenclature for labeling dilutions
from the maintenance concentrate
Dilution from
maintenance concentrate Vol/vol label No. Color
Maintenance concentrate 1:1 1 Red
10-fold 1:10 2 Yellow
100-fold 1:100 3 Blue
1000-fold 1:1000 4 Green
10,000-fold 1:10,000 5 Silver
addition to the labeled dilution from the maintenance concentrate
(vol/vol), a numbering system, a color-coding
system, or an alphabetical system should be used. If this
uniform labels system is used, it is essential that it be
used in the same way by all physicians to reduce potential
administration errors by staff unfamiliar with the labeling
system. If the current labeling system is different, the transition
toward the uniform labeling system should be gradually
phased in to reduce potential errors, and the staff
involved with preparation and administration of allergen
immunotherapy should be involved with the planning of
this transition.
If a numbering system is used, the highest concentration
should be numbered 1. This is necessary to provide
consistency in labeling because if larger numbers are
used to indicate more concentrated extracts, the number of
the maintenance concentrate would vary from patient to
patient depending on the number of dilutions made. If a
color-coding system is used, it should be consistent (eg,
the highest concentration should be red, the next highest
yellow, followed by blue, green, and silver in that order)
(Figs 3 and 4).
Regardless of the labeling system used for indicating
dilutions from the maintenance concentrate, the specific
contents of each allergen immunotherapy extract should
be listed separately. The volume and concentration of each
of its constituents should be listed on the immunotherapy
prescription form.
Consistency is essential as a basis for adoption of a
standardized system. Some allergists/immunologists,
however, have found it helpful to use letters for designating
different component mixtures of extracts (eg, trees [T],
grasses [G], and molds [M] [see Appendix 2]).