Drug kinetics after multiple dosing Pharmacokinetics of multiple dose • The purpose of the multiple dosing is to maintain a desired plasma level of drugs for long periods of time. • The plasma level obtained from each succeeding dose is always higher than those obtained from the previous dose since some drug remains in the plasma when repeated doses are administered. • Since the rate of elimination is proportional to the amount of drug in the body, it increases with the increasing amount of drug until it approaches the rate of input (rate of input=rate of output). • At this point the amount reaches a plateau in the body. (Rate of input=rate of output). • The main difference is the fluctuation in the plasma concentration due to multiple dosing. 2 • Dosage regimen: – size of the drug dose – frequency o...
