Intraindividual variability of paracetamol absorption kinetics after a semi-solid meal in healthy volunteers

The absorption kinetics of paracetamol is dependent on gastric emptying and its measurement was proposed as a non-invasive method to estimate gastric emptying rate. The objective of this study was to evaluate the intraindividual variability of paracetamol absorption kinetics after a semi-solid meal. The pharmacokinetics of paracetamol was studied on two occasions in 15 healthy volunteers without Helicobacter pylori antibodies. A 1-g dose of paracetamol was given as a solution together with a standardised semi-solid meal and the subjects stayed in the supine position. For most of the subjects, the time course of paracetamol concentrations was similar on the two occasions. The intraindividual variability was low, with coefficients of variation of 38.3%, 8.0% and 3.8% for time to maximum plasma concentration, maximum concentration and area under the plasma concentration - time curve until 6 h, respectively. The assessment of paracetamol absorption kinetics is reproducible when the drug is given together with a semi-solid meal in Helicobacter pylori-negative healthy subjects.