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MDP-25 (kit for the preparation of technetium tc 99m medronate injection) (Kit for the Preparation of Technetium Tc 99m Medronate) may be used as a bone imaging agent to delineate areas of altered osteogenesis.
DOSAGE AND ADMINISTRATION
The recommended adult dose, after reconstitution with oxidant-free sodium pertechnetate Tc 99m, is 370 to 740 megabecquerels (10 to 20 millicuries [200 μCi/kg]) by slow intravenous injection over a period of 30 seconds. Optimum scanning time is 1 to 4 hours post-injection.
To minimize the contribution of the bladder content to the image, the patient should void immediately before imaging is started.
The patient dose should be measured by a suitable radioactivity calibration system immediately prior to administration.
Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration. The solution should not be used if cloudy.
The estimated absorbed radiation doses to an average patient (70 kg) from an intravenous injection of a maximum dose of 740 megabecquerels (20 millicuries) of Technetium Tc 99m Medronate are shown in Table 4. The effective half-life was assumed to be the physical half-life for all calculated values.
Table 4 RADIATION DOSES2
|Tissue||Absorbed Radiation Dose|
|mGy/740 MBq||rads/20 mCi|
|2 hr. void||26.0||2.60|
|4.8 hr. void||62.0||6.20|
|2 hr. void||2.4||0.24|
|4.8 hr. void||3.4||0.34|
|2 hr. void||1.6||0.16|
|4.8 hr. void||2.2||0.22|
|2Method of calculation: “S” Absorbed Dose per Unit Cumulated Activity for Selected Radionuclides and Organs, MIRD Pamphlet No. 11, 1975|
MDP-25, Kit for the Preparation of Technetium Tc 99m Medronate Injection
Product No. 500661 (30 vials)
Available in boxes consisting of 30 reaction vials, each vial containing in lyophilized form, sterile and non-pyrogenic:
|Medronic Acid||25.0 mg|
|Stannous Chloride Dihydrate (minimum)||2.0 mg|
|(Maximum tin as stannous chloride dihydrate)||3.0 mg|
|p-Aminobenzoic Acid||5.0 mg|
The pH is adjusted to 6.8 to 6.9 with HCI or NaOH prior to lyophilization. The vials are sealed under an atmosphere of nitrogen. Radioassay information labels with radiation warning symbol and a package insert are supplied in each box.
Store the unreconstituted reaction vials at 25°C (77°F); excursions permitted between 15° and 30°C (59° to 86°F). After labeling with Technetium Tc 99m, the reconstituted product should be stored at 25°C (77°F) in the original vial, and be placed in a suitable lead shield. Excursions permitted between 15° and 30°C (59° to 86°F). Discard the reconstituted solution after 12 hours.
NOTE: Use aseptic procedures throughout and take precautions to minimize radiation exposure by use of suitable shielding. Use waterproof gloves during the following preparation procedure.
MDP-25 (kit for the preparation of technetium tc 99m medronate injection) reaction vials are intended for the preparation of multiple doses of technetium Tc-99m medronate and the entire contents of the vial should not be used as a single dose.
Before reconstituting a vial, it should be inspected for cracks and/or a melted plug or any other indication that the integrity of the vacuum seal has been compromised.
To prepare Technetium Tc 99m Medronate:
- Remove the central metal disc from a reaction vial and swab the closure with either an alcohol swab or a suitable bacteriostatic agent.
- Place the reaction vial in a suitable lead vial shield (minimum wall thickness
1/8 inch) which has a fitted lead cap. Obtain 2 to 10 mL of sterile, non-pyrogenic
sodium pertechnetate Tc 99m, using a shielded syringe.
The recommended maximum amount of Technetium Tc 99m to be added to a reaction vial is 37.0 gigabecquerels (1000 mCi). Sufficient sodium pertechnetate is to be used for the reconstitution of a reaction vial to ensure that the dose of medronate administered does not exceed 10 mg. Sodium pertechnetate Tc 99m solutions containing an oxidizing agent are not suitable for use.
- Using a shielded syringe, add the sodium pertechnetate Tc 99m solution to the reaction vial aseptically.
- Place the lead cap on the reaction vial shield and agitate the shielded reaction vial until the contents are completely dissolved. The solution must be clear and free of particulate matter before proceeding.
- Assay the product in a suitable calibrator, record the radioassay information on the label with radiation warning symbol, and apply it to the reaction vial.
- Withdrawals for administration must be made aseptically using a shielded sterile syringe and needle. Since the reaction vials contain nitrogen to prevent oxidation of the complex, they should not be vented. If repeated withdrawals are made, minimize the replacement of contents with room air.
The following steps should be followed to ensure that each reconstituted of technetium Tc 99m medronate contains between 1 and 10 mg of medronic acid.
Vr = Final volume of in the vial in mL after reconstitution.
C = Concentration of Medronic Acid in mg/mL.
Max. V = Maximum volume to be used for one dose in mL.
Min. V =Minimum volume to be used for one dose in mL.
- Prior to reconstitution, determine the radioactive concentration of the sodium pertechnetate Tc 99m.
- Note the volume and activity added to the vial. It should be between 1.85 – 37.0 GBq (50 – 1000 mCi) in 1 to 10 mL.
- Calculate the concentration (C) of Medronic acid in the vial after reconstitution.
C (mg/mL) = 25 mg ÷ Vr (mL)
- To ensure that the dose contains a maximum of 10 mg, the following formula
should be used to calculate the maximum volume (Max. V) to be dispensed as one
Max. V (mL) = 10 mg ÷ C (mg/mL)
- To ensure that a minimum dose of 1 mg is dispensed, the following formula
should be used to calculate the minimum volume (Min. V) to be dispensed as one
Min. V = 1 ÷ C
7. The finished preparation should be stored at 25°C (77°F); excursions permitted between 15° and 30°C (59° to 86°F) when not in use and discarded after 12 hours. It should also be stored during its life in a suitable lead shield.
This reagent kit is approved by the U.S. Nuclear Regulatory Commission for distribution to persons licensed to use by-product material identified in §35.200 to 10 CFR Part 35, to persons who have a similar authorization issued by an Agreement State, and, outside the United States, to persons authorized by the appropriate authority.
NDC 65174-660-30 (30 vials)
Manufactured by: DRAXIMAGE, a division of DRAXIS Specialty Pharmaceuticals Inc. Kirkland, Quebec H9H 4J4 Canada.
Last reviewed on RxList: 12/8/2010
This monograph has been modified to include the generic and brand name in many instances.
Additional MDP-25 Information
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