INDICATIONS
Greer Standardized Mite (Dermatophagoides farinae and/or
Dermatophagoides pteronyssinus) Extracts are allergenic extracts indicated for:
- skin test diagnosis of mite allergy
- treatment of patients with mite-induced allergic asthma,
rhinitis and conjunctivitis.
For Immunotherapy, patients must show hypersensitivity to
Dermatophagoides farinae (D. farinae) or Dermatophagoides pteronyssinus (D.
pteronyssinus) based on their clinical history, allergen exposure history, and
skin test reactivity.
DOSAGE AND ADMINISTRATION
Do not inject intravenously.
Greer Standardized Mite extracts are diluted with sterile
diluent for allergenic extracts when used for intradermal testing or
subcutaneous immunotherapy. Dosages vary by mode of administration, and by individual
response and tolerance. Parenteral drug products should be inspected visually
for particulate matter and discoloration prior to administration, whenever
solution and container permit.
Greer Standardized Mite Extracts should be a light brown
solution that is free of particulate matter. If particulate matter is observed
then the solution should be discarded.
Diagnostic Testing
For diagnosis of a patient with a suspected allergy to
either species of dust mite (D. farinae or D. pteronyssinus), diagnostic skin
testing should include the standardized mite mixture or the singlespecies mite
extracts.
- If a skin test with the standardized mite mixture elicits
a positive reaction, then the single-species mite extracts can be used to
determine the degree of sensitivity to each, and to guide in the selection of
extracts and their concentration for immunotherapy, if indicated.
- A positive skin test reaction to any allergen must be
interpreted in light of the patient's history of symptoms, the time of year,
and known exposure to environmental allergens.
Percutaneous Skin Testing
For percutaneous (scratch, prick, or puncture) testing,
use 10,000 Allergy Units/mL Greer Standardized Mite Extract stock concentrate
in dropper vials. If patient is suspected of having exquisite sensitivity, such
as anaphylaxis, to certain foods and drugs, initiate percutaneous testing with
several serial 10-fold dilutions of the usual test concentration.
- For scratch tests, scarify the skin, and then apply one
drop of the extract to the scratch.
- For prick tests, place one drop of extract on the skin
and pierce through the drop into the skin with a slight lifting motion.
- For puncture tests, place one drop of extract on the skin
and pierce through the drop perpendicular to the skin.
When using percutaneous test devices, follow the
directions provided with the test devices.
Include a positive control to detect false negative
responses to skin testing, which may occur if serum levels of antihistamines
remain from prior medication administration [see DRUG INTERACTIONS]. A glycerinated
histamine phosphate diluted to 10mg/mL (6mg/mL histamine base) may be used as
the positive control.
Include a negative control to detect false positive
responses, which can occur when the patient has a non-specific reaction to the
diluent. A 50% gylcerosaline solution may be used as the negative control. Read
skin tests 15-20 minutes after exposure. Record the induration (wheal) and
erythema (flare) response by noting the longest diameter of each, or by the sum
of the longest erythema diameter and the mid-point orthogonal diameters of
erythema (ÓE).
Percutaneous testing devices often have their own grading
systems, as these devices may cause different degrees of trauma to the skin and
deliver different volumes of allergenic extract. Follow grading instructions
for the device used.
Intradermal Skin Testing
Intradermal tests are commonly used when the reaction to
percutaneous testing is negative or equivocal but the patient has a strong
clinical history of symptoms triggered by exposure to a specific allergen.
Because immediate systemic reactions are more common with
intradermal testing, prescreening with percutaneous testing is a practical
safety measure.1
Dilute the stock concentrate with sterile diluent. Use
saline with human serum albumin (HSA), buffered saline, or saline. If
prescreening is not done, or if patients are expected to be high risk,
precautions should be observed since some patients have experienced anaphylaxis
and death.
- Patients who do not react to percutaneous skin testing
should be tested intradermally at a starting dose of 0.02 to 0.05 mL of a 50
Allergy Units/mL extract dilution.
- Patients suspected of being highly allergic should first
receive a test dose of 0.02 to 0.05 mL of a 0.05 Allergy Units/mL extract
dilution.
- If the intial dose test is negative, subsequent
intradermal tests using increasingly stronger doses may be performed up to the
maximum recommended strength of 200 Allergy Units / mL.
- If percutaneous skin testing was not performed, include a
positive control to detect false negative responses to skin testing, which may
occur if serum levels of antihistamines remain from prior medication administration
[see DRUG INTERACTIONS]. A glycerinated histamine phosphate diluted to
0.5 mg/mL (0.18 mg/mL histamine base ) or aqueous histamine phosphate 0.275
mg/mL (0.1 mg/mL histamine base) may be used as the positive control.
- If percutaneous skin testing was not performed, include a
negative control to detect false positive responses, which can occur when the
patient has a non-specific reaction to the diluent. A 1% glycerin in 0.9%
saline solution may be used as the negative control.
- Measure the wheal-and-flare response after 15-20 minutes,
which may be graded using various methods as described in the instructions for
the device used.
The mean dose of Greer dust mite allergen required to
elicit a positive intradermal test result (OE3 50 mm) in a total of
83 mite puncture test positive (OE3 20 mm) persons is shown in
Table1.
Table 1: Intradermal Reactivity to Mite Allergens
Allergen |
Number of Persons |
Dose to Elicit 50 mm Sum of Diameter Erythema Reaction |
Mean (AU*/mL) |
Range (AU/mL) |
D. farinae |
46 |
0.00856 |
0.00004 - 1.75935 |
D. pteronyssinus |
37 |
0.00570 |
0.00002 - 1.36341** |
* Allergy Units
** Data is available on file with Greer |
Immunotherapy
Subcutaneous injection only.
Subcutaneous injections for immunotherapy should be
prepared by dilution of stock concentrate based on patient’s reactivity. Stock
concentrations of Greer Standardized Mite Extract are available in 5,000 Allergy
Units/mL, 10,000 Allergy Units/mL, 30,000 Allergy Units/mL for immunotherapy.
See Table 2 for dilution preparation. Also see Dosage Modification
Guidelines.
- The initial dose of the extract should be based on the
percutaneous test reactivity. In patients who appear to be exquisitely
sensitive by history and skin test, the initial dose of the extract should be 0.1
mL of a 0.005 to 0.05 Allergy Units/mL dilution. Patients with lesser
sensitivity may be started at a 0.5 to 5 Allergy Units/mL dilution.
- The dose of allergenic extract is increased at each
injection by no more than 50% of the previous dose, and the next increment is
governed by the response to the last injection.
- Large local reactions which persist for longer than 24
hours are generally considered an indication for repeating the previous dose or
reducing the dose at the next administration.
- Any evidence of a systemic reaction is an indication for
a significant reduction (at least 75%) in the subsequent dose. Repeated
systemic reactions, even of a mild nature, are sufficient reason for the cessation
of further attempts to increase the reaction-causing dose.
- Severe reactions require a decrease in the next dose by
at least 50%. Proceed cautiously in subsequent dosing.
- A maximum tolerated maintenance dose should be selected
based on the patient's clinical response and tolerance. Doses larger than 0.2
mL of the concentrate are rarely administered because an extract in 50%
glycerin may cause discomfort upon injection.
- Since the two mite species tend to cross-react, consider
the total Allergy Units content in determining the maximum maintenance dose of
the mixture.
Dosage Modifications Guidelines For Immunotherapy
The following conditions may indicate a need to withhold
or reduce the dosage of immunotherapy. In situations prompting dose reduction,
once the reduced dose is tolerated, a cautious increase in dosage can be
attempted. Immunotherapy should be withheld or reduced in dosage if the
following concurrent conditions exist:
- Severe symptoms of rhinitis and/or asthma;
- Infection accompanied by fever; or
- Exposure to excessive amounts of clinically relevant
allergen prior to a scheduled injection.
Changing to a different lot of extract: All extracts lose
potency over time. A fresh extract may have an effective potency that is
substantially greater than that of older extracts. Therefore, the first dose
from the fresh vial should not exceed a 25% increase of the previous dose or a
75% reduction of the previous dose, assuming both extracts contain comparable
amounts of allergen, defined by Allergy Units.
Unscheduled Gaps between Treatments: Patients may lose
tolerance for allergen injections during prolonged periods between doses, thus
increasing their risk for an adverse reaction. The duration of tolerance
between injections varies from patient to patient.
- During the build-up phase, when patients receive
injections 1 to 2 times per week, it is customary to repeat or even reduce the
extract dosage if there has been a substantial time interval betweeninjections.
This depends on 1) the concentration of allergen immunotherapy extract that is
to be administered, 2) a previous history of systemic reactions, and 3) the
degree of variation from the prescribed interval of time, with longer intervals
since the last injection leading to greater reductions in the dose to be
administered. This suggested approach to dose modification due to unscheduled
gaps between treatments during the build-up phase is not based on published
evidence. The individual physician should use this or a similar protocol as a
standard operating procedure for the specific clinical setting.
- Similarly, if large unscheduled gaps occur during
maintenance therapy, it may be necessary to reduce the dosage. The individual
physician should devise a protocol as a standard operating procedure for his or
her specific clinical setting in determining how to modify doses of allergen immunotherapy
due to unscheduled gaps in treatment.
The extract previously used is from another manufacturer:
Since manufacturing processes and sources of raw materials differ among
manufacturers, the interchangeability of extracts from different manufacturers
cannot be assured. The starting dose of the extract from a different
manufacturer should be greatly decreased even though the extract is the same
formula and dilution. In general, a dose reduction of 50- 75% of the previous
dose should be adequate, but each situation must be evaluated separately
considering the patient's history of sensitivity, tolerance of previous
injections, and other factors. Dose intervals should not exceed one week when
rebuilding dose.
The previous extract has expired or is near expiry: The
dating period for allergenic extracts indicates the time that they can be
expected to remain potent under ideal storage conditions (2° - 8°C) [see HOW
SUPPLIED/Storage And Handling]. Some loss of potency occurs even
when stored under ideal conditions, therefore extracts should not be stored
beyond the expiration date. Instead, a new lot should be used (see "Changing
to a different lot of extract”, above)
Changing from non-stabilized to human serum albumin (HSA)
stabilized diluents: Allergenic extracts diluted with HSA and 0.4% phenol are
more potent than extracts diluted with diluents that do not contain stabilizers.
When switching from a non-stabilized to an HSA stabilized diluent, consider
lowering the dose for immunotherapy.
Administration Of Immunotherapy
- Administer immunotherapy by subcutaneous injection in the
lateral aspect of the arm or thigh. Avoid injection directly into any blood
vessel.
- The optimal interval between doses of allergenic extract
varies among individuals. Injections are usually given 1 or 2 times per week
until the maintenance dose is reached, at which time the injection interval is
increased to 2,3, and finally 4 weeks.
- Because most adverse reactions occur within 30 minutes
after injection, patients should be kept under observation for at least 30
minutes.2 For high risk patients 30 minutes of observation may not be
sufficient.
Dilution Preparation
To prepare dilutions for intradermal testing and
immunotherapy, start with a 5,000, 10,000, or 30,000 Allergy Units/mL stock
concentrate, and prepare a 1:10 dilution by adding 0.5 mL of concentrate to 4.5
mL of sterile aqueous diluent. Subsequent dilutions are made in a similar
manner (see Table 2).
Table 2: Ten-fold Dilution Series for intradermal
testing and immunotherapy
Dilution |
Extract |
Diluent |
AU*/mL |
AU/mL |
AU/mL |
0 |
Concentrate |
|
5,000 |
10,000 |
30,000 |
1 |
0.5 mL Concentrate |
4.5 mL |
500 |
1,000 |
3.000 |
2 |
0.5 mL Dilution 1 |
4.5 mL |
50 |
100 |
300 |
3 |
0.5 mL Dilution 2 |
4.5 mL |
5 |
10 |
30 |
4 |
0.5 mL Dilution 3 |
4.5 mL |
0.5 |
1 |
3 |
5 |
0.5 mL Dilution 4 |
4.5 mL |
0.05 |
0.1 |
0.3 |
6 |
0.5 mL Dilution 5 |
4.5 mL |
0.005 |
0.01 |
10.03 |
*Allergy Units |
HOW SUPPLIED
Dosage Forms And Strengths
For immunotherapy, concentrated extracts are diluted in
normal saline, buffered saline, albumin saline or 10% glycerosaline. For
intradermal testing extracts may be diluted in normal saline, buffered saline,
or albumin saline.
Greer Standardized Mite Extract D. farinae and Greer
Standardized Mite Extract D. pteronyssinus are supplied as stock concentrates
containing 10,000 Allergy Unit/mL and Greer Standardized Mite Extract mixture
(D. farinae and D. pteronyssinus) is supplied as a stock mixture concentrate
containing 5,000 Allergy Units/mL of each species for use in percutaneous skin
testing.
Greer Standardized Mite Extract D. farinae and Greer
Standardized Mite Extract D. pteronyssinus are supplied as stock concentrates
containing 5,000, 10,000, or 30,000 Allergy Unit/mL. Greer Standardized Mite
Extract mixture (D. farinae and D. pteronyssinus) is supplied as a stock
mixture concentrate containing 5,000 and 15,000 Allergy Units/mL of each
species for use in intradermal testing and immunotherapy.
Mite extracts in 50% Glycero-Coca solution are supplied
as follows:
D. farinae: 5,000 Allergy Unit/mL, 10, 30, and 50 mL
vials NDC 22840-0033
D. farinae: 10,000 Allergy Unit/mL, 10, 30, and 50 mL
vials NDC 22840-0034
D. farinae: 30,000 Allergy Unit/mL, 10, 30, and 50 mL
vials NDC 22840-0038
D. pteronyssinus 5,000 Allergy Unit/mL, 10, 30, and 50 mL
vials NDC 22840-0035
D. pteronyssinus: 10,000 Allergy Unit/mL, 10, 30, and 50
mL vials NDC 22840-0036
D. pteronyssinus: 30,000 Allergy Unit/mL, 10, 30, and 50
mL vials NDC 22840-0039
D. farinae/D. pteronyssinus 5,000 Allergy Unit/mL each
species, 10, 30, mixture: and 50 mL vials NDC 22840-0037
D. farinae/D. pteronyssinus 15,000 Allergy Unit/mL each
species, 10, 30, mixture: and 50 mL vials NDC 22840-0040
D. farinae: 10,000 Allergy Unit/mL, 5 mL percutaneous NDC
22840-0034 test vial D. pteronyssinus: 10,000 Allergy Unit/mL, 5 mL
percutaneous NDC 22840-0036 test vial
D. farinae/D. pteronyssinus 5,000 Allergy Unit/mL each
species, 5 mL mixture: percutaneous test vial NDC 22840-0037
Storage And Handling Section
Store dust mite extract at 2°-8°C (36° to 46°F).
Keep dust mite extract at 2°- 8°C (36° to 46°F) during
office use.
Dilutions of concentrated extract result in a glycerin
content of less than 50% which results in reduced stability of the extracts.
1:100 dilutions should be kept no longer than a month, and more dilute
solutions no more than a week. The potency of a dilution can be checked by skin
test comparison to a fresh dilution of the extract on a known mite allergic
individual.
THIS KIT CONTAINS:
5 x 5mL empty colored vials
1 x 30mL normal saline
1 x 5mL Std. Dermatophagoides Pteronyssinus Allergen
Extract
REFERENCES
2. Cox L, Li JT, Nelson H, Lockey R. Allergen immunotherapy:
A practice parameter second update. J Allergy Clin Immunol 2007; 120:S25-S85.
Packaged By: Alvix Laboratories, LLC, 6601 Sunplex Dr. Ocean
Springs, MS 39564, 1.888.526.5449. Revised: Jul 2015