TechneScan PYP

Generic name: technetium tc 99m pyrophosphate
Dosage form: injection, powder, lyophilized, for solution

TechneScan PYP Description

Technescan™ PYP™ (Kit for the Preparation of Technetium Tc 99m Pyrophosphate Injection) is a sterile, non-pyrogenic, diagnostic radiopharmaceutical suitable for intravenous administration after reconstitution with sterile sodium pertechnetate Tc 99m injection or sterile 0.9% sodium chloride injection.

Each 10 milliliter reaction vial contains 11.9 milligrams sodium pyrophosphate, 3.2 milligrams (minimum) stannous chloride (SnCl2•2H2O) and 4.4 milligrams (maximum) total tin expressed as stannous chloride (SnCl2•2H2O) in lyophilized form under an atmosphere of nitrogen. Prior to lyophilization the pH is adjusted with hydrochloric acid. The pH of the reconstituted drug is between 4.5 and 7.5. No bacteriostatic preservative is present.

The precise structures of the stannous-pyrophosphate and technetium-stannous-pyrophosphate complexes are not known at this time.

PHYSICAL CHARACTERISTICS

Technetium Tc 99m decays by isomeric transition with a physical half-life of 6.02 hours.1The principal photon that is useful for detection and imaging is listed in Table 1.

The specific gamma ray constant for technetium Tc 99m is 0.78 R/mCi-hr at 1 cm. The first half-value thickness of lead (Pb) for technetium Tc 99m is 0.017 cm. A range of values for the relative attenuation of the radiation emitted by this radionuclide that results from interposition of various thicknesses of Pb is shown in Table 2. For example, the use of 0.25 cm of Pb will decrease the external radiation exposure by a factor of about 1000.