Deterministic Chaos and Wash-Out Determination in Crossover Trials

Background: Key elements of crossover studies are the determination of the wash-out (clearance) period. The purpose of this work is an attempt to implement and justify the use of deterministic chaos theory for estimating the wash-out value and reference the obtained values to the currently applicable rules. Results/methodology: The elliptical model of drug wash-out was presented to prove the hypothesis. Pharmacokinetic profiles were used for the analysis, obtained from healthy subjects during 12 studies. Conclusion: On the grounds of these calculations it may be concluded that the pharmacokinetics of xenobiotics, such as drugs, is a product of deterministic chaos.