SODIUM IODIDE I 123

Sodium Iodide I 123 (Na 123 I) for diagnostic use is supplied in capsules for oral administration. The capsules are available in strengths of 3.7 and 7.4 megabecquerels (MBq) (100 and 200 μCi) I-123 at time of calibration. The radionuclidic composition at calibration is not less than 97.0 percent I-123, not more than 2.9 percent I-125 and not more than 0.1 percent Te-121. The radionuclidic composition at expiration time is not less than 87.2 percent I-123, not more than 12.4 percent I-125 and not more than 0.4 percent Te-121. The ratio of the concentration of I-123 and I-125 changes with time. Graph 1 shows the minimum concentration of I-123 as a function of time and Graph 2 shows the maximum concentration of I-125 as a function of time. Graph 1. Radionuclidic Concentration of I-123 PERCENT OF TOTAL RADIOACTIVITY: IODINE-123 Graph 2. Radionuclidic Concentration of I-125 PERCENT OF TOTAL RADIOACTIVITY: IODINE-125 Graph 1 Graph 2 Physical Characteristics Iodine-123 decays by electron capture with a physical half-life of 13.2 hours Kocher, David C., Radioactive Decay Data Tables. DOE/TIC-11026, 122 (1981). . The 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 83.4 159 External Radiation The specific gamma ray constant for I-123 is 1.6 R/hr-mCi at 1 cm. The first half-value thickness of lead (Pb) for I-123 is 0.005 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 1.63 cm of lead will decrease the external radiation exposure by a factor of about 1,000. Table 2. Radiation Attenuation by Lead Shielding Shield Thickness (Pb), cm Coefficient of Attenuation 0.005 0.10 0.88 1.63 2.48 0.5 10 -1 10 -2 10 -3 10 -4 Note that these estimates of attenuation do not take into consideration the presence of radionuclidic contaminants. To correct for physical decay of I-123, the fractions that remain at selected intervals after the time of calibration are shown in Table 3. Table 3. Iodine I-123 Decay Chart: Half-Life 13.2 Hours Hours Fraction Remaining Hours Fraction Remaining *Time of Calibration 0* 3 6 9 12 15 1.000 0.854 0.730 0.623 0.533 0.455 18 21 24 27 30 0.389 0.332 0.284 0.242 0.207

Administration of Sodium Iodide I 123 Capsules is indicated as a diagnostic procedure to be used in evaluating thyroid function and/or morphology.

The recommended oral dose for the average patient (70 kg) is 3.7 to 14.8 MBq (100 to 400 μCi). The lower part of the dosage range 3.7 MBq (100 μCi) is recommended for uptake studies alone, and the higher part 14.8 MBq (400 μCi) for thyroid imaging. The determination of I-123 concentration in the thyroid gland may be initiated at six hours after administering the dose and should be measured in accordance with standardized procedures. The patient dose should be measured by a suitable radioactivity calibration system immediately prior to administration. The capsules can be utilized up to 30 hours after calibration time and date. Thereafter, discard the capsules in accordance with standard safety procedures. The user should wear waterproof gloves at all times when handling the capsules or container. Radiation Dosimetry The estimated absorbed radiation doses to several organs of an average patient (70 kg) from oral administration of the maximum dose of 14.8 MBq (400 μCi) of I-123 are shown in Table 4 for thyroid uptakes of 5, 15, and 25%. For comparison at these three values of thyroid uptake, the estimated radiation doses from doses of 3.7 MBq (100 μCi) I-131, also used as thyroid imaging agent, are also included. Table 4. Absorbed Radiation Dose Estimates as a Function of Maximum Thyroid Uptake for Sodium Iodide I-123 * at Time of Calibration and Expiry Compared to Sodium Iodide I-131 Estimated Radiation Absorbed Doses I-123 mGy/14.8 MBq (rads/400 μCi) I-131 mGy/3.7 MBq (rads/100 μCi) Target Organ Maximum Thyroid Uptake (%) TOC TOE * Concentration at Time of Calibration: 97% I-123, 2.9% I-125, 0.1% Te-121 Concentration at Time of Expiry: 87.2% I-123, 12.4% I-125, 0.4% Te-121 Metabolic model in MIRD Dose Estimate Report 5 followed for I-123 and I-125 Metabolic model in ICRP 30 followed for Te-121 † Bladder voiding interval 4.8 hours. Bladder † 5 1.7 (0.17) 1.7 (0.17) 2.9 (0.29) 15 1.6 (0.16) 1.6 (0.16) 2.7 (0.27) 25 1.4 (0.14) 1.5 (0.15) 2.4 (0.24) Stomach Wall 5 0.96 (0.096) 0.98 (0.098) 1.7 (0.17) 15 0.89 (0.089) 0.91 (0.091) 1.5 (0.15) 25 0.82 (0.082) 0.85 (0.085) 1.4 (0.14) Small Intestine 5 0.70 (0.070) 0.71 (0.071) 1.2 (0.12) 15 0.65 (0.065) 0.67 (0.067) 1.1 (0.11) 25 0.60 (0.060) 0.62 (0.062) 0.99 (0.099) Liver 5 0.089 (0.0089) 0.13 (0.013) 0.16 (0.016) 15 0.10 (0.010) 0.18 (0.018) 0.28 (0.028) 25 0.11 (0.011) 0.24 (0.024) 0.41 (0.041) Ovaries 5 0.18 (0.018) 0.19 (0.019) 0.18 (0.018) 15 0.17 (0.017) 0.18 (0.018) 0.18 (0.018) 25 0.16 (0.016) 0.18 (0.018) 0.17 (0.017) Skeleton 5 0.11 (0.011) 0.16 (0.016) 0.12 (0.012) 15 0.12 (0.012) 0.18 (0.018) 0.18 (0.018) 25 0.14 (0.014) 0.21 (0.021) 0.24 (0.024) Red Marrow 5 0.12 (0.012) 0.16 (0.016) 0.15 (0.015) 15 0.12 (0.012) 0.18 (0.018) 0.21 (0.021) 25 0.13 (0.013) 0.19 (0.019) 0.27 (0.027) Testes 5 0.076 (0.0076) 0.089 (0.0089) 0.12 (0.012) 15 0.072 (0.0072) 0.087 (0.0087) 0.12 (0.012) 25 0.068 (0.0068) 0.085 (0.0085) 0.12 (0.012) Thyroid 5 25 (2.5) 75 (7.5) 260 (26) 15 77 (7.7) 230 (23) 780 (78) 25 130 (13) 410 (41) 1300 (130) Total Body 5 0.11 (0.011) 0.16 (0.016) 0.24 (0.024) 15 0.14 (0.014) 0.25 (0.025) 0.47 (0.047) 25 0.17 (0.017) 0.35 (0.035) 0.70 (0.070)

To date there are no known contraindications to the use of Sodium Iodide I 123 Capsules.

Although rare, reactions associated with the administration of sodium iodide isotopes for diagnostic use include, in decreasing order of frequency, nausea, vomiting, chest pain, tachycardia, itching skin, rash and hives.

Storage and Handling The contents of the vial are radioactive and adequate shielding and handling precautions must be maintained. Dispense and preserve capsules in tightly-closed containers that are adequately shielded. Store at controlled room temperature 20° to 25°C (68° to 77°F). Storage and disposal of Sodium Iodide I 123 Capsules should be controlled in a manner that is in compliance with the appropriate regulations of the government agency authorized to license the use of this radionuclide. Curium and the Curium logo are trademarks of a Curium company. ©2018 Curium US LLC. All Rights Reserved. Manufactured by: Curium US LLC Maryland Heights, MO 63043 Made in USA A601I0 R12/2018 CURIUM™