GALLIUM- gallium citrate ga-67 injection

Gallium by

Drug Labeling and Warnings

Gallium by is a Prescription medication manufactured, distributed, or labeled by Lantheus Medical Imaging, Inc.. Drug facts, warnings, and ingredients follow.

Drug Details [pdf]

SPL UNCLASSIFIED SECTION

FOR DIAGNOSTIC USE

DESCRIPTION

Gallium Citrate Ga 67 Injection is supplied in isotonic solution as a sterile, non-pyrogenic diagnostic radiopharmaceutical for intravenous administration. Each milliliter of the isotonic solution contains 74 MBq (2 mCi) of Gallium Ga 67 on the calibration date, as a complex formed from 9 ng Gallium Chloride Ga 67, 2 mg of sodium citrate, 6.8 mg sodium chloride, and 9 mg benzyl alcohol/mL added as preservative. The pH is adjusted to between 4.5-8 with hydrochloric acid and/or sodium hydroxide solution. Gallium Ga 67, with a half-life of 78.3 hours, is cyclotron produced by the proton irradiation of enriched zinc oxide, is essentially carrier-free and contains negligible concentrations of other radioactive isotopes.

The radionuclidic composition at calibration time is ≥99.89% Gallium Ga 67, ≤0.01% Gallium Ga 66 and ≤0.1% due to other radiocontaminants, each expressed as a percentage of total activity. The radionuclidic composition at expiration time is ≥99.89% Gallium Ga 67, essentially zero (0.0002%) Gallium Ga 66 and essentially zero of other radiocontaminants each expressed as a percentage of total activity.

The chemical structure for Gallium Citrate is shown below:

Physical Characteristics

Gallium Ga 67 decays to stable Zinc Zn 67 by electron capture with a physical half-life of 78.3 hours.1

TABLE 1. Principal Radiation Emission Data

Radiation	Mean %/Disintegration	Mean Energy (keV)
Gamma-3	35.7	93.3
Gamma-4	19.7	184.6
Gamma-6	16.0	300.2

1 Kocher, David C., "Radioactive Decay Data Tables", DOE/TIC-11026 (1981).

External Radiation

The specific gamma ray constant for Gallium Ga 67 is 5.58 microcoulombs/Kg-hr-MBq (0.80R/hr-mCi) at 1 cm. The first half value thickness of lead is 0.066 cm. A range of values for the relative attenuation of the radiation emitted by this radionuclide that results from the interposition of various thicknesses of Pb is shown in Table 2. For example, the use of 0.41 cm of Pb will decrease the external radiation exposure by a factor of 10.

TABLE 2. Radiation Attenuation By Lead Shielding

cm of Pb	Radiation Attenuation Factor	cm of Lead ( Pb)	Radiation Attenuation Factor
0.066	0.5	2.5	10-3
0.41	10-1	4.8	10-4
1.2	10-2

To correct for physical decay of this radionuclide, the fractions that remain at selected time intervals after the time of calibration are shown in Table 3.

TABLE 3. Gallium Ga 67 Decay Chart Half-Life 78.3 Hours

Hours	Fraction Remaining	Hours	Fraction Remaining	Hours	Fraction Remaining
* Calibration Time
0*	1.00	42	0.69	84	0.48
6	0.95	48	0.65	90	0.45
12	0.90	54	0.62	96	0.43
18	0.85	60	0.59	108	0.38
24	0.81	66	0.56	120	0.35
30	0.77	72	0.53	132	0.31
36	0.73	78	0.50	144	0.28
				156	0.25
				168	0.23