Knowledge of Pharma

INTRODUCTION:  Pharmacokinetics, sometimes abbreviated as PK, (from Ancient Greek pharmakon "drug" and kinetikos "to do with motion") is dedicated to the determination of the fate of substances administered externally to a living organism. Pharmacokinetics is the science of the kinetics of drug absorption, distribution, and elimination (ie, excretion and metabolism). The description of drug distribution and elimination is often termed drug disposition.  Pharmacokinetics is often studied in conjunction with pharmacodynamics.  Pharmacodynamics explores what a drug does to the body, whereas pharmacokinetics explores what the body does to the drug. Pharmacokinetics includes the study of the mechanisms of absorption and distribution of an administered drug, the rate at which a drug action begins and the duration of the effect, the chemical changes of the substance in the body (e.g. by enzymes) and the effects and routes of excretion of the metabolites of the dru

BIOEQUIVALENCE: It‘s commonly observed that there are several formulations of the same drug, in the same dose, in similar dosage form and meant to be given by the same route. in order to ensure clinical performance of such drug products, bioequivalence studies should be performed. TYPES  OF  EQUIVALENCE Chemical Equivalence:  When 2 or more drug products contain the same labeled chemical substance as an active ingredient in the same amount.  Pharmaceutical Equivalence:  When two or more drug products are identical in strength, quality, purity, content uniformity, disintegration and dissolution characteristics; they may however differ in excipients.  Bioequivalence:  A relative term which denotes that the drug substance in two or more dosage forms, reaches the systemic circulation at the same relative rate and to the same relative extent i.e., their plasma concentration time profiles will be identical without significant statistical difference.  Therapeutic Equi