The disposition of paracetamol following an oral dose of 1.0 g was compared in 10 healthy volunteers, 7 patients with moderate chronic renal failure and 6 patients with end stage renal failure on maintenance haemodialysis. Paracetamol absorption was normal in the patients with renal failure. The mean plasma half-life of paracetamol from 2 to 8 h was similar in the 3 groups (2.1 to 2.3 h) but from 8 to 24 h it disappeared much more slowly in the renal failure patients (half-life 11.7 compared with 4.9 h in the healthy volunteers). Plasma concentrations of paracetamol glucuronide and sulphate conjugates were greatly increased in the patients with moderate renal failure and the mean plasma half-lives were 30.5 and 21.8 h respectively compared with about 3 h in the healthy volunteers. Plasma concentrations of these metabolites were even higher in the dialysis patients and there was no significant fall over 24 h. The cysteine and mercapturic acid conjugates of paracetamol could only be measured in plasma in the patients with renal failure and concentrations were very low. The fractional urinary recovery of paracetamol and its glucuronide, sulphate, cysteine and mercapturic acid conjugates was similar in healthy volunteers and patients with moderate renal failure.(ABSTRACT TRUNCATED AT 250 WORDS)

Two premix products containing the endectocide ivermectin were compared for pharmacokinetic profiles and bioequivalence in young pigs. Test and reference articles were administered to individual pigs in-feed at 12-h intervals for a total of 14 doses. Plasma concentration-time profiles were compared after provision of the final doses of medicated feed, by which time steady-state concentrations of ivermectin had been achieved. The pharmacokinetic variables monitored were peak concentration (Cmax ), area under the curve (AUC)0-last , elimination half-life of the terminal phase (T1/2 λz) and average steady-state concentration (Css ), determined by noncompartmental analysis. Logarithmic transformation of the variables was carried out when appropriate. Analysis of data by the Classic Method yielded confidence intervals of 80.59-114.47 (for AUC0-last ), 90.38-119.68 (for Cmax ) and 84.70-111.96 (for Css ). It was concluded that the two articles were bioequivalent for ivermectin.