ASSESSMENT OF BLOOD LEVEL WITH CONTROLLED-RELEASE DOSAGE FORMS - EFFECT OF THE RATE-CONSTANT OF ELIMINATION OF THE DRUG

Prediction of the drug level in the volume of distribution was made us ing a numerical model taking into account the following facts: the kin etics of drug release out of the dosage form along the gastrointestina l tract, the kinetics of absorption in the blood compartment and the k inetics of elimination. Various parameters intervene significantly for a given dosage form. Some emphasis was Placed upon the rate of elimin ation of the drug which appears to be the main characteristic for the drug, especially when it is delivered through controlled release dosag e forms. The rate of release of the drug out of the dosage form, as we ll as the dose frequency and the gastrointestinal transit time were al so considered. The drug level in the plasma was expressed by the amoun t of drug as a fraction of the amount of drug initially located in the dosage form.