A model for short term drug absorption studies; comparison of sulphadiazine tablets.
The four parameter equation, applicable to drug absorption kinetics over a limited time period, has been used to interpret plasma concentration, time results following oral dosage with three different formulations of sulphadiazine tablets, to each of five subjects. Assessment parameters for the formulations, the time for ten percent absorption, the time interval between 10-90% absorption and the plasma concentration with no disposition (relative availability) have been estimated. Intersubject variation obscured many of the differences between formulations. To blank off this variation, plasma concentrations at each time were averaged and then random variation corresponding to the error of the assay method was applied so as to generate a number of sets of data which including the mean concentrations was equal to the number of sets in the original measurements. Kinetic analysis of these sets indicated a number of significant differences between the formulations.