Tc 99m Medronate

Technetium Tc 99m Medronate Injection may be used as a bone imaging agent to delineate areas of altered osteogenesis.

None known.

This class of compounds is known to complex cations such as calcium. Particular caution should be used with patients who have, or may be predisposed to hypocalcemia (i.e., alkalosis). Preliminary reports indicate impairment of brain scans using Sodium Pertechnetate Tc 99m Injection which have been preceded by a bone scan using an agent containing stannous ions. The impairment may result in false-positive or false-negative brain scans. It is recommended, where feasible, that brain scans precede bone imaging procedures. Alternatively, a brain imaging agent such as Technetium Tc 99m Pentetate Injection 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 .)

General Contents of the vial are intended only for use in the preparation of Technetium Tc 99m Medronate Injection and are NOT to be administered directly to the patient. Technetium Tc 99m Medronate Injection as well as other radioactive drugs must be handled with care, and appropriate safety measures should be used to minimize radiation exposure to the patient and clinical personnel consistent with proper patient management. To minimize radiation dose to the bladder, the patients should be encouraged to drink fluids and to void immediately before the examination and as often thereafter as possible for the next 4 to 6 hours. Technetium Tc 99m Medronate Injection should be formulated within six (6) hours prior to clinical use. Optimal imaging results are obtained 1 to 4 hours after administration. The finding of an abnormal concentration of radioactivity implies the existence of underlying pathology, but further study is required to distinguish benign from malignant lesions. The image quality may be adversely affected by obesity, old age, or impaired renal function. The components of the kit are sterile and non-pyrogenic. It is essential to follow directions carefully and to adhere to strict aseptic procedures during preparation. Technetium Tc 99m labeling reactions involved depend on maintaining the stannous ion in the reduced state. Hence, Sodium Pertechnetate Tc 99m Injection containing oxidants should not be used. The preparation contains no bacteriostatic preservative. Technetium Tc 99m Medronate Injection should be stored at 20-25ºC (68-77ºF) and discarded 6 hours after reconstitution. The solution should not be used if the contents are cloudy. Vials are sealed under nitrogen: air or oxygen is harmful to the contents of the vials and the vials should not be vented. The components of the Kit for the Preparation of Technetium Tc 99m Medronate for Injection are supplied sterile and non-pyrogenic. Aseptic procedures normally employed in making additions and withdrawals for sterile, non-pyrogenic containers should be used during addition of the pertechnetate solution and the withdrawal of doses for patient administration. Shielding should be utilized when preparing Technetium Tc 99m Medronate Injection. No special handling is required for the non-radioactive drug product. Radiopharmaceuticals should be used only by physicians who are qualified by training and experience in the safe use and handling of radionuclides, and whose experience and training have been approved by the appropriate government agency authorized to license the use of radionuclides. Drug Interactions 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. In patients with high levels of these cations caused by concomitant medications, particularly patients receiving iron infusions, consider performing an imaging study with technetium Tc 99m medronate injection once the cation levels have normalized (e.g., after 3 to 5 half-lives of the cation). (See WARNINGS .) Carcinogenesis, Mutagenesis, Impairment of Fertility No long-term animal studies have been performed to evaluate carcinogenic potential or whether Technetium Tc 99m Medronate Injection affects fertility in males or females. Mutagenesis studies have not been conducted. Pregnancy Animal reproduction and teratogenicity studies have not been conducted on Technetium Tc 99m Medronate Injection. It is also not known whether Technetium Tc 99m Medronate Injection can cause fetal harm when administered to a pregnant woman or can affect reproductive capacity. Technetium Tc 99m Medronate Injection should be given to a pregnant woman only if clearly needed. Ideally, examinations using radiopharmaceuticals, especially those elective in nature, on a woman of childbearing capability, should be performed during the first few (approximately 10) days following the onset of menses. Nursing mothers Technetium Tc 99m Medronate Injection is excreted in human milk during lactation; therefore, formula feeding should be substituted for breast feeding. Pediatric Use Safety and effectiveness in pediatric subjects have not been established.

Several adverse reactions due to Technetium Tc 99m Medronate Injection have been reported. These were usually hypersensitivity reactions characterized by itching, various skin rashes, hypotension, chills, nausea, and vomiting. There have also been rare cases of dizziness and asthenia associated with the use of Technetium Tc 99m Medronate.

Technetium Tc 99m Medronate Injection is excreted in human milk during lactation; therefore, formula feeding should be substituted for breast feeding.

Safety and effectiveness in pediatric subjects have not been established.