Version July 2025
Glomerular filtration evaluation:
Note: Dosing based on a 70 kg patient.
Single injection: IV: 10 to 30 microcuries (0.37 to 1.11 MBq). Note: To minimize radioactive iodine uptake by the thyroid gland, administer thyroid protective agents (eg, Lugol's solution) for 1 to 2 days prior to the single injection test method.
Continuous infusion: IV: 20 to 100 microcuries (0.74 to 3.7 MBq).
There are no dosage adjustments provided in the manufacturer's labeling.
There are no dosage adjustments provided in the manufacturer's labeling.
There are no adverse reactions listed in the manufacturer's labeling.
Central venous line administration
Special handling:
• Radiopharmaceutical: Use appropriate precautions for handling, disposal, and minimizing exposure to patients and health care personnel. Use only under supervision of individuals with experience/training in the handling of radioactive materials approved by the applicable regulatory authority.
Other warnings/precautions:
• Appropriate use: Administration: Avoid rapid or bolus-like injections.
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Solution, for injection:
Glofil-125: 250-300 µCi/mL (4 mL) [contains benzyl alcohol]
No
Radiopharmaceutical; use appropriate precautions for handling and disposal. For IV administration as single injection or continuous infusion at usual rate of 0.5 mL/minute. To minimize radioactive iodine uptake by the thyroid gland, administer thyroid protective agents (eg, Lugol's solution) for 1 to 2 days prior to the single injection test method. An oral water load of 20 mL/kg should be started 1 hour prior to and continued until the test is complete for the single injection method. An oral water load of 1,500 mL should be started 2 hours prior to the continuous infusion method.
Glomerular filtration evaluation: Radiopharmaceutical imaging agent used for evaluation of glomerular filtration in the diagnosis or monitoring of patients with renal disease.
Radiopharmaceutical: Use appropriate precaution for handling, disposal, and minimizing exposure to patients and healthcare personnel. Use under supervision of experienced personnel. Should be stored in original lead container or adequate radiation shield.
None known.
There are no known significant interactions.
Animal reproduction studies have not been conducted.
In general, testing with a radiopharmaceutical during pregnancy should consider the half-life of the radiopharmaceutical, if alternative tests are available, and if the test can reasonably be delayed (ARSAC 2024).
It is not known if iodine I-125 iothalamate is present in breast milk.
Radioiodine is present in breast milk. The manufacturer recommends substituting formula feedings for breast milk following administration of iodine I-125 iothalamate. In general, when breast milk concentrations of a radiopharmaceutical are not known, breastfeeding should be interrupted until breast milk samples are tested and levels are within an acceptable range. Consider the half-life of the radiopharmaceutical, if alternative tests are available, and if the test can reasonably be delayed (ARSAC 2024).
Metabolism: Decays by electron capture
Half-life elimination: ~0.07 days; Physical half-life: ~60 days
