Pharmacokinetics Essay

OVERVIEW

The word Pharmacokinetics was coined from Greek work Pharmakon means drugs and poisons.

Wargner in 1968 and 1975 define Pharmacokinetic as the time course of drug and metabolite concentrations or amounts in biological fluids, tissues and excreta, and also of pharmacological response, and to construct suitable models to interpret such data. In pharmacokinetics, the data are analysed using a mathematical representation of a part or the whole of an organism.

Gilbaldi and Levy in 1976 gave related definition, they defined pharmacokinetics as the study of a characterisation of time course of drug absorption, distribution, metabolism and excretion, and with the relationship of these processes to the intensity and time course of therapeutic and adverse effects of drugs.

ORIGINS OF THE SUBJECT MATTER

The first attempt into what led to pharmacokinetics/pharmacodynamics was first describe by

Buchanan Andrew in his work ”Physiological effects of the inhalation of ether ”. Buchanan pointed out that for short ether inhalations, the speed of recovery was related to redistribution of ether in the body and went further to calculate the amount of ether inhaled, exhaled and retained during induction with this short acting anesthetic (Buchanan 1847, Butler, 1964).

In 1913, Michaelis-Menten equation used to describe enzyme kinetics was published by Michaelis and Menten and equation had been used to describe the elimination kinetics of drugs (Michaelis and Menten 1913).

Another wonderful work on the origin of the subject matter is from Swedish investigators.

In 1924 Windmark and Tandberg published equations now known as (a ) the one -compartment open model with bolus intravenous injection and multiple doses administered at uniform inter- vals... ... middle of paper ...

... Schaldemose, 1959).

Another great contribution to Pharmacokinetic during this period are the (a) introduction of the curve-fitting method based on polyexponential equations (Perl, 1960); and (b) introduction of the use of analog computer for fitting and simulating pharmacokinetics data and in model building (Garrett et al, 1960; Wiegand and Taylor , 1960).

The first symposium with a title incorporating the term pharmacokinetcs, was held in Bors- tel, Germany in 1962. The proceeding of this symposium were potent forces is disseminating pharmacokinetic idea .

Experimental verification of Wagner 1976 articles which suggest that, if a panel of subjects were administered the same dose of drug by the same route of administration and resulting blood concentration time data were fitted by polyexponential equations with the statistically optimum number of terms per data set