Clearance of Drug (Pharmacokinetics Part 14) | Dr. Shikha Parmar скачать в хорошем качестве

Clearance of Drug (Pharmacokinetics Part 14) | Dr. Shikha Parmar

Clearance of Drug (Pharmacokinetics Part 14) by Dr. Shikha Parmar Pharmacokinetics is currently defined as the study of the time course of drug absorption, distribution, metabolism, and excretion. Pharmacokinetics of a drug depends on patient-related factors as well as on the drug’s chemical properties. Some patient-related factors (eg, renal function, genetic makeup, sex, age) can be used to predict the pharmacokinetic parameters in populations. For example, the half-life of some drugs, especially those that require both metabolism and excretion, may be remarkably long in the elderly In pharmacology (and more specifically pharmacokinetics), absorption is the movement of a drug from the site of administration to the bloodstream. Before drugs can be clinically effective, they must be absorbed. Absorption is the process of a drug moving from its site of delivery into the bloodstream. The chemical composition of a drug, as well as the environment into which a drug is placed, work together to determine the rate and extent of drug absorption. Absorption involves several phases. First, the drug needs to be introduced via some route of administration (oral, topical-dermal, etc.) and in a specific dosage form such as a tablet, capsule, solution and so on. Drug absorption is determined by the drug’s physicochemical properties, formulation, and route of administration. Dosage forms (eg, tablets, capsules, solutions), consisting of the drug plus other ingredients, are formulated to be given by various routes (eg, oral, buccal, sublingual, rectal, parenteral, topical, inhalational). Regardless of the route of administration, drugs must be in solution to be absorbed. Thus, solid forms (eg, tablets) must be able to disintegrate and deaggregate. Pharmacokinetic- “What does BODY 1 do to the DRUG 2” we have simple interchanged the BODY and DRUG to make a definition. And as per the definition, our body responds to any drug by giving ADME effects. 1. A Stands for - Absorption 2. D stands for - Distribution 3. M stands for - Metabolism 4. E stands for- Elimination Drug excretion is the process of eliminating a drug from the body. A drug, which is either biologically active itself or a prodrug, may be excreted in its original chemical state. Alternatively, all or a portion of a drug may undergo chemical modification and be eliminated as biologically active, or inactive, metabolites (see the record on Drug Biotransformation) renal excretion plays an important role in eliminating unchanged drugs or their metabolites into the urine. A major characteristic of compounds excreted in urine is that they are polarized (i.e., charged) and water-soluble. Drugs that are lipid-soluble are not readily removed by the kidneys and require hepatic metabolism (e.g., phase I and phase II biotransformation reactions) to increase their water solubility for possible urinary excretion. Description Source: Wkipedia