Dose proportionality of iopromide pharmacokinetics and tolerability after i.v. injection in healthy volunteers.

Twelve healthy male volunteers participated in a single-blind, randomised, placebo-controlled cross-over study of i.v. iopromide in doses of 15 g iodine or 80 g iodine infused over a period of 15 min. The volunteers were observed for three days during which time blood samples, urine and faeces were collected. The terminal disposition phase half-life of iopromide was 2 h and 1.9 h, and the total clearance was 110 and 103 ml.min-1 at the lower and at the higher dose levels, respectively. The steady state volume of distribution was 16 and 17 l, indicating predominantly extracellular distribution of iopromide. Statistical analysis (one-sided t-test) showed that all the target parameters (AUC, half-life and urinary excretion) were equivalent at both dose levels, indicating dose proportionate, first order kinetics of iopromide over the large dose range tested. Iopromide was well tolerated after both doses.