Pharmacokinetics of iopentol in healthy volunteers

Iopentol is a new non-ionic contrast medium. In order to study the pharmacokinetic properties, iopentol 350 mg I/ml was administered intravenously to healthy male volunteers at 3 dose levels (0.3, 0.6 and 1.2 g I/kg body weight). To evaluate renal excretion all subjects were given chromium-51-ethylenediaminetetraacetic acid (51Cr-EDTA) additionally to iopentol. The highest dose level group also received saline and 51Cr-EDTA about 3 weeks prior to iopentol. Serum, urine and faeces were sampled at different time intervals. Unmetabolized iopentol was excreted almost entirely in urine during the first 24 hours by means of glomerular filtration. A small fraction (2%) of the dose was excreted in faeces. No dose dependent pharmacokinetics was observed up to doses of 1.2 g I/kg body weight. The pharmacokinetic properties of iopentol make it a well suited contrast medium for vascular use.