Sodium Iothalamate I-125 Injection
FDA Drug Information • Also known as: Glofil-125
- Brand Names
- Glofil-125
- Route
- INTRAVENOUS
- Dosage Form
- INJECTION, SOLUTION
- Product Type
- HUMAN PRESCRIPTION DRUG
Description
DESCRIPTION General GLOFIL-125 (Sodium Iothalamate I-125 Injection) is a sterile, nonpyrogenic aqueous injection containing approximately 1 mg sodium iothalamate per mL, and 0.9 percent benzyl alcohol as a preservative. The radioactive concentration of the material is 250-300 µCi/mL as of the calibration date. Sodium bicarbonate and hydrochloric acid are present for pH adjustment.
What Is Sodium Iothalamate I-125 Injection Used For?
INDICATIONS AND USAGE GLOFIL-125 (Sodium Iothalamate I-125 Injection) is indicated for evaluation of glomerular filtration in the diagnosis or monitoring of patients with renal disease.
Dosage and Administration
Dosage The suggested dose range employed in the average patient (70 kg) is as follows: Continuous intravenous infusion: 20 to 100 μCi (0.74-3.7 megabecquerels) (Sigman, et al (1) method). Single intravenous injection: 10 to 30 µCi (0.37-1.11 megabecquerels) Cohen, et al (2) method) The patient dose should be measured by a suitable radioactivity calibration system immediately prior to administration. Technique Continuous intravenous infusion Sigman 1 method I. Preparation: Adequate diuresis (a urine flow exceeding 3 mL/min.) is established, preferably by an oral water load of 1,500 mL two hours prior to the beginning of the clearance study. 2. It is not necessary to withhold breakfast or admit the patient the night before. II. Procedure: After the establishment of adequate diuresis, a number 14 or 16 French Foley catheter is aseptically inserted into the bladder. An intravenous infusion of Lactated Ringers (Hartmanns) solution is started in each arm, one to maintain a site for injection of the GLOFIL-125, the other to serve as a site for serial withdrawal of blood. A two-way stopcock connects the needle and intravenous tubing of each arm. The dose is equally divided into (1) an intravenous priming dose to be injected as is and (2) a sustaining dose to be diluted in 30 to 60 mL of isotonic sodium chloride, depending on how many collection periods are anticipated. The priming dose is slowly injected into one arm. This is immediately followed by infusion of the sustaining solution through the same site, usually at the rate of 0.5 mL/min., by means of an automatic pump. During this infusion, the Lactated Ringers solution in the same arm is discontinued, and 40 to 45 minutes are allowed for equilibration in order to reach a state of constant plasma concentration of radioactivity. After attaining equilibrium, consecutive 15 minute collection periods are started. From the arm opposite the injection site, 5 mL of blood (allowing duplicate plasma counting volumes) is drawn six minutes prior to the midpoint of each collection period, placed in heparinized tubes, mixed, and centrifuged. The blood samples may be obtained through the two-way stopcock after discarding the first 30 mL aspirated into the syringe. This 30 mL contains the contents of the tubing, including infusion fluid, and must be cleared in order to obtain an undiluted blood sample. If desired, this step may be eliminated and blood samples obtained by direct venipuncture. During each collection period, total urine must be accurately collected and the volume accurately measured. Three such consecutive collection periods are sufficient for most clinical studies. III. Clearance Calculations: 1. Aliquots (1 mL each) of plasma and urine from each collection period are counted in a standard gamma-ray scintillation well detector. 2. All counts are corrected for background activity. 3. Glomerular filtration rate is calculated by the formula C=UV/P, in which: C = glomerular filtration rate in mL/min U=...
Side Effects (Adverse Reactions)
ADVERSE REACTIONS None Reported
Warnings and Precautions
WARNINGS None known
Contraindications
CONTRAINDICATIONS GLOFIL-125 should not be administered via a central venous line.
How Supplied
HOW SUPPLIED Identity No. 1000, GLOFIL-125 is a clear, colorless, sterile, and nonpyrogenic solution available as a 4 mL vial. It is supplied in a concentration of approximately 1 mg/mL sodium iothalamate (range is 0.5–2.0 mg sodium iothalamate per mL), with a radioactivity concentration of 250 to 300 μCi/mL at the time of calibration. Benzyl alcohol 0.9%, is added as a preservative. Sodium bicarbonate and hydrochloric acid are added for pH adjustment. The calibration and expiration dates are shown on the label.
About This Information
This drug information is sourced from FDA-approved labeling via the openFDA database. It is intended for educational and reference purposes only. This is not medical advice. Always consult your healthcare provider before making decisions about medication. Drug information may be updated by the FDA; check with your pharmacist for the most current information.
What are side effects?
Side effects are unwanted reactions that can occur when taking a medication. They range from mild (headache, nausea) to severe (allergic reactions, organ damage). Not everyone experiences side effects, and severity varies. Report any concerning side effects to your doctor.
What are drug interactions?
Drug interactions occur when a medication is affected by another drug, food, or supplement. Interactions can make medications less effective or cause dangerous side effects. Always tell your doctor about all medications and supplements you take.