Biopharmaaceutics is a major branch of the pharmaceutical science; it concerns the relationship between the physical and chemical properties of a drug in a dosage form and the pharmacologic, toxicologic, or clinical response observed after its administration. The study of biopharmaceutics has been extended beyond that of a descriptive discipline by the development of pharmacokinetics, which concerns the study and characterization of the time course of drug absorption, distributionship of these processes to the intensity and time course of therapeutic and adverse effects of drugs. Pharmacokinetics involves the application of mathematics andbiochemistry in a physiologic and pharmacologic context. The development of clinical pharmacokinetics is the culmination and logical outcome of advances in the areas of pharmacokinetics, clinical pharmacology, toxicology, analytic chemistry, biopharmaceutics, and therapeutics. Simply stated, clinical pharmacokinetics is a health sciences discipline that deals with the application of pharmacokinetics to the safe and effective therapeutic management of the individual patient.