HUMAN PHARMACOKINETICS OF IODIXANOL

The pharmacokinetic properties of the x-ray contrast medium, iodixanol, a new nonionic dimer, were investigated in a phase I study including 40 healthy male volunteers. Iodixanol (300 mg I/mL) was administered intravenously (i.v.) at four dose levels - 0.3, 0.6, 0.9, and 1.2 g iodine (I)/kg body weight - and saline was given as a control. Cr-51-EDTA was given concomitantly with iodixanol at all dose levels to study renal excretion of iodixanol. Mean half-lives were 26 and 131 minutes in the distribution and elimination phase, respectively. Apparent volume of distribution was 0.28 1/kg body weight, indicating distribution to extracellular fluid only. Within 24 hours after injection, 97% of the dose was excreted unmetabolized in the urine via glomerular filtration. The excretion in feces was 1.2% of the dose. The parameters calculated were independent of the given dose. The pharmacokinetics of iodixanol are comparable with those reported for other intravascular contrast media.