UCL Discovery

Abstract

Absorption rate profiles of two sustained-release theophylline formulations have been calculated using Quantified maximum Entropy, and alternative approach to calculate pharmacokinetic parameters. There is no evidence in the data that the distribution of theophylline is in any other than in the central compartment. In general, model concentration profiles fitted to the experimental data in a satisfactory manner. However, the absolute absorption rate profiles derived are not smooth, which could be a general characteristics of the pellet preparations. The Mean Absorption Times (MAT) of the pellet formulations are more than four times those of an oral solution. This indicates the success in prolonging the drug release. Although one formulation provides a longer Mean Absorption Time, there is no significant difference in the relative extent of absorption of the preparations when compared to an oral solution. The absence of the requirement for a fixed pharmacokinetic model provides an approach which is more flexible than alternative methods.