Overview
DESCRIPTION Iopamidol Injection, USP formulations are stable, aqueous, sterile, and nonpyrogenic solutions for intrathecal administration. Each mL of Iopamidol Injection, USP, 41% provides 408 mg iopamidol with 1 mg tromethamine and 0.26 mg edetate calcium disodium. The solution contains approximately 0.029 mg (0.001 mEq) sodium and 200 mg organically bound iodine per mL.
Mechanism of Action
CLINICAL PHARMACOLOGY The pharmacokinetics of intravenously administered iopamidol in normal subjects conform to an open two-compartment model with first order elimination (a rapid alpha phase for drug distribution and a slow beta phase for drug elimination). The elimination serum or plasma half-life is approximately two hours; the half-life is not dose dependent. No significant metabolism, deiodination, or biotransformation occurs. Iopamidol is rapidly absorbed into the bloodstream from cerebrospinal fluid (CSF); following intrathecal administration, iopamidol appears in plasma within one hour and virtually all of the drug reaches the systemic circulation within 24 hours.
Indications
- INDICATIONS AND USAGE Iopamidol Injection is indicated for intrathecal administration in adult neuroradiology including myelography (lumbar, thoracic, cervical, total columnar), and for contrast enhancement of computed tomographic (CECT) cisternography and ventriculography. Iopamidol Injection, 41% is indicated for thoraco-lumbar myelography in children over the age of two years.
Common Doses
- 3000 mg
- 2400 mg
Dosage
DOSAGE AND ADMINISTRATION In adults a solution that is approximately isotonic (Iopamidol Injection, 41%) is recommended for examination of the lumbar region. For movement of the contrast medium to distant target areas the more concentrated Iopamidol Injection, 61% preparation should be used to compensate for dilution of Iopamidol Injection with cerebrospinal fluid. The usual recommended adult dose range for iopamidol is 2000-3000 mg iodine. Iopamidol formulated to contain more than 300 mgI/mL should not be used intrathecally in adults.
Contraindications
- CONTRAINDICATIONS Intrathecal administration of corticosteroids with iopamidol is contraindicated. Because of overdosage considerations, immediate repeat myelography in the event of technical failure is contraindicated (see interval recommendation under DOSAGE AND ADMINISTRATION ). Myelography should not be performed in the presence of significant local or systemic infection where bacteremia is likely.
Side Effects
- ADVERSE REACTIONS The most frequently reported adverse reactions following intrathecal administration of iopamidol are headache, nausea, vomiting, and musculoskeletal pain. These reactions usually occur 1 to 10 hours after injection, almost all occurring within 24 hours. They are usually mild to moderate in degree, lasting for a few hours and usually disappearing within 24 hours. Rarely, headaches may be severe or persist for days. Headache is often accompanied by nausea and vomiting, and tends to be more frequent and persistent in patients not optimally hydrated.
Interactions
- Drug Interactions Other drugs should not be admixed with iopamidol (see CONTRAINDICATIONS , and DOSAGE AND ADMINISTRATION : Drug Incompatibilities ).