EFFECT OF DRUG TRANSIT-TIME BETWEEN EXCHANGE LOCUS WITH PLASMA AND SAMPLING SITE

In pharmacokinetic models used to describe the behavior of drugs in li ving organisms, generally neither the amount of drug flowing in pipes between compartments nor the transfer delay between the plasma-lymph e xchange areas and a site of measurement are taken into account. Severa l former publications dealt with exchanges between two or more differe nt organs assuming that the blood flow was constant or that the variat ion of the lymphatic flow was negligible or noting that the amount of drug present in pipes was not easily taken into account.In this articl e, we deal with concentration in a site of interstitial exchanges with regard to concentration in a sampling site with a varying blood flow, assuming that the transit time depends both on the fluid flow and the path length through pipes. In all considered cases, the plasma concen tration profile may be highly altered by a change in the flow rate.