Technetium Tc 99M Medronate
FDA Drug Information • Also known as: Kit For The Preparation Of Technetium Tc 99M Medronate, Technetium Tc 99M Medronate
- Brand Names
- Kit For The Preparation Of Technetium Tc 99M Medronate, Technetium Tc 99M Medronate
- Route
- INTRAVENOUS
- Dosage Form
- INJECTION, POWDER, FOR SOLUTION
- Product Type
- HUMAN PRESCRIPTION DRUG
Description
DRAXIMAGE® MDP-25 Kit for the Preparation of Technetium Tc 99m Medronate Injection For Intravenous Use DIAGNOSTIC – FOR SKELETAL IMAGING DESCRIPTION The kit consists of reaction vials which contain the sterile, non-pyrogenic,non-radioactive ingredients necessary to produce Technetium Tc 99m Medronate Injection for diagnostic use by intravenous injection. MDP-25 reaction vials are intended to be used as multidose vials. Each 10 mL MDP-25 reaction vial contains 25.0 mg medronic acid and not less than 2.0 mg of stannous chloride dihydrate (maximum total tin expressed as stannous chloride dihydrate 3.0 mg) and 5.0 mg of p-aminobenzoic acid in lyophilized form under an atmosphere of nitrogen. The pH is adjusted to 6.8 to 6.9 with HCI or NaOH prior to lyophilization. The addition of sterile, non-pyrogenic, and oxidant-free sodium pertechnetate Tc-99m sterile solution produces a rapid labeling which is essentially quantitative and which remains stable in vitro throughout the 12-hours life of the preparation. No bacteriostatic preservative is present. The structural formula of medronic acid is: PHYSICAL CHARACTERISTICS Technetium Tc-99m decays by isomeric transition with a physical half-life of 6.02 hours. 1 The principal photon that is useful for detection and imaging studies is listed in Table 1. Table 1 Principal Radiation Emission Data Radiation Mean % / Disintegration Energy (keV) Gamma-2 89.07 140.5 EXTERNAL RADIATION The specific gamma ray constant for Tc-99m is 0.78 R/mCi-hr at 1 cm. The first half value layer is 0.017 cm of lead. To facilitate control of the radiation exposure from millicurie amounts of this radionuclide, the use of a 0.25 cm thickness of lead will attenuate the radiation emitted by a factor of about 1000. A range of values for the relative attenuation of the radiation emitted by this radionuclide that results from interposition of various thicknesses of lead is shown in Table 2. Table 2 Radiation Attenuation by Lead Shielding Shield Thickness...
What Is Technetium Tc 99M Medronate Used For?
INDICATIONS AND USAGE MDP-25 (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
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. RADIATION DOSIMETRY 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 Doses 2 Tissue Absorbed Radiation Dose mGy/740 MBq rads/20 mCi Total Body Total Bone Red Marrow Kidneys Liver Bladder Wall 2 hr. void 4.8 hr. void Ovaries 2 hr. void 4.8 hr. void Testes 2 hr. void 4.8 hr. void 1.3 7.0 5.6 8.0 0.6 26.0 62.0 2.4 3.4 1.6 2.2 0.13 0.70 0.56 0.80 0.06 2.60 6.20 0.24 0.34 0.16 0.22 2 Method of calculation: “S” Absorbed Dose per Unit Cumulated Activity for Selected Radionuclides and Organs, MIRD Pamphlet No. 11, 1975 HOW SUPPLIED 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. STORAGE Store the unreconstituted reaction vials at 25ºC (77ºF); excursions permitted between 15° and 30ºC (59° to 86ºF). After labeling with Technetium Tc-99m, the reconstituted product should be stored at 25ºC (77ºF) in the original vial, and be placed in a suitable lead shield. Excursions permitted between 15° and 30ºC (59° to 86ºF). Discard the reconstituted solution after 12 hours. DIRECTIONS 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 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...
Side Effects (Adverse Reactions)
ADVERSE REACTIONS Several cases of allergic dermatological reactions have been reported in association with the use of Technetium Tc 99m Medronate. Several reactions have also been reported in association with other radiopharmaceuticals of the diphosphonate class, particularly Technetium Tc 99m Medronate. These are usually hypersensitivity reactions characterized by itching, various skin rashes, hypotension, chills, nausea, fever, and vomiting. One death secondary to cardiac arrhythmia following the administration of Technetium Tc 99m Medronate has been reported. In addition, one case of cardiac arrest in a patient also undergoing pulmonary function testing one and one-half hours after the performance of a bone scan using Technetium Tc 99m Medronate has been reported.
Warnings and Precautions
WARNINGS This class of compounds is known to complex cations such as calcium. Particular caution should be used with patients who have, or who may be predisposed to, hypocalcemia (i.e., alkalosis). The contents of the kit before preparation are not radioactive. However, after the sodium pertechnetate Tc-99m is added, adequate shielding of the final preparation must be maintained. Preliminary reports indicate impairment of brain images using Sodium Pertechnetate Tc 99m Injection which have been preceded by bone imaging using an agent containing stannous ions. The impairment may result in false-positive or false-negative brain images. It is recommended, where feasible, that brain imaging using Sodium Pertechnetate Tc 99m Injection precede bone imaging procedures. Alternatively, a brain imaging agent such as technetium Tc-99m pentetate may be employed. The biodistribution of technetium Tc 99m medronate may be altered in the presence of high levels of certain cations (iron, calcium, and aluminum). This may result in reduced uptake of radionuclide in the skeleton and increased extraosseal uptake, which may potentially degrade imaging quality. High levels of these cations may be caused by concomitant medications or medical conditions (e.g., iron overload, hypercalcemia, etc.). Most cases were observed after iron infusion. (See PRECAUTIONS, Drug Interactions. )
Contraindications
CONTRAINDICATIONS None known.
About This Information
This drug information is sourced from FDA-approved labeling via the openFDA database. It is intended for educational and reference purposes only. This is not medical advice. Always consult your healthcare provider before making decisions about medication. Drug information may be updated by the FDA; check with your pharmacist for the most current information.
What are side effects?
Side effects are unwanted reactions that can occur when taking a medication. They range from mild (headache, nausea) to severe (allergic reactions, organ damage). Not everyone experiences side effects, and severity varies. Report any concerning side effects to your doctor.
What are drug interactions?
Drug interactions occur when a medication is affected by another drug, food, or supplement. Interactions can make medications less effective or cause dangerous side effects. Always tell your doctor about all medications and supplements you take.