Overview
11 DESCRIPTION 11.1 Drug Characteristics Thallous Chloride Tl 201 Injection is a sterile, radioactive diagnostic drug for intravenous use. Each mL contains 37 MBq (1 mCi) thallous chloride Tl 201 at calibration time and the following inactive ingredients: 9 mg sodium chloride and 0.9% (v/v) benzyl alcohol. The pH is adjusted to between 4.5 to 7.0 with hydrochloric acid and/or sodium hydroxide.
Mechanism of Action
12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Thallous chloride Tl 201 with no carrier added accumulates in viable myocardium in a manner analogous to that of potassium. Experiments in healthy subjects using labeled microspheres have shown that the myocardial distribution of thallous chloride Tl 201 correlates with regional perfusion. In clinical studies, Thallous Chloride Tl 201 images have been found to visualize areas of infarction as “cold” or nonlabeled regions that were confirmed by electrocardiographic and enzyme changes. Regions of transient myocardial ischemia corresponding to areas perfused by coronary arteries with partial stenoses have been visualized when Thallous Chloride Tl 201 Injection was administered in conjunction with an exercise stress test.
Indications
- 1 INDICATIONS AND USAGE Thallous Chloride Tl 201 Injection is indicated for use with planar scintigraphy or single-photon emission computed tomography (SPECT) for the following applications: Myocardial perfusion imaging in adults for the diagnosis of coronary artery disease by localization of: Non-reversible defects (myocardial infarction) Reversible defects (myocardial ischemia) when used in conjunction with exercise or pharmacologic stress Localization of sites of parathyroid hyperactivity pre- and post-operatively in adults with elevated serum calcium and parathyroid hormone levels...
Common Doses
- Refer to label
Dosage
2 DOSAGE AND ADMINISTRATION • For myocardial perfusion imaging: Planar 37 MBq to 74 MBq (1 mCi to 2 mCi) ( 2.2 ) SPECT 74 MBq to 111 MBq (2 mCi to 3 mCi) ( 2.2 ) For localization of parathyroid hyperactivity, planar or SPECT: 75 MBq to 130 MBq (2 mCi to 3.5 mCi) Administer by intravenous injection. ( 2.2 ) See full prescribing information for administration and imaging instructions and radiation dosimetry information. ( 2.3 , 2.4 ) 2.
Contraindications
- 4 CONTRAINDICATIONS None. None
Side Effects
- 6 ADVERSE REACTIONS The following clinically significant adverse reactions are described elsewhere in the labeling: Hypersensitivity Reactions [see Warnings and Precautions ( 5.1 )] Risk Associated with Stress Testing [see Warnings and Precautions ( 5.2 )] Injection Site Reactions and Tissue Damage [see Warnings and Precautions ( 5.4 )] The following adverse reactions associated with the use of Thallous Chloride Tl 201 Injection were identified in clinical studies or postmarketing reports.
Interactions
- No major interactions listed on the FDA label. Always consult a healthcare professional.