Drug metabolism refers to how quickly certain medicines are processed by your body. How quickly you process these drugs can affect whether a medicine will work for you, or whether you may feel side-effects. ... The 5 different types of metabolizer status are described below.
Most drugs must pass through the liver, which is the primary site for drug metabolism. Once in the liver, enzymes convert prodrugs to active metabolites or convert active drugs to inactive forms. The liver’s primary mechanism for metabolizing drugs is via a specific group of cytochrome P-450 enzymes.
Drug metabolism is the metabolic breakdown of drugs by living organisms, usually through specialized enzymatic systems. More generally, xenobiotic metabolism (from the Greek xenos "stranger" and biotic "related to living beings") is the set of metabolic pathways that modify the chemical structure of xenobiotics, which are compounds foreign to an organism's normal biochemist...
Drug Metabolism. The textbook definition of metabolism states that it refers to “a set of biochemical processes within any living organism that allows that living organism to grow, reproduce, repair damage and respond to its environment.”. Drug metabolism on the other hand specifically refers to the chemical alteration that any drug undergoes inside the body.
SITES OF DRUG METABOLISM. The liver is the main organ of drug metabolism. This fact figures prominently in the phenomenon known as the first-pass effect.Orally administered drugs are often absorbed in the gastrointestinal (GI) tract and transported directly to the liver via the portal circulation (Fig. 4-1).In this manner, the liver has the opportunity to metabolize drugs before they reach the ...
Types of drug kinetics. Zero order kinetics: : The rate of metabolism and/or elimination remains constant and is independent of the concentration of a drug (e.g., metabolism of alcohol) First order kinetics: : The rate of metabolism and/or elimination is directly proportional to the plasma concentration of the drug (applies to most drugs)
Two types of enzymes are involved in metabolism: Phase I Metabolism. These enzymes modify the drug chemically by processes such as oxidation, reduction and hydrolysis or by the removal and addition of an active group. Phase II Metabolism
Biotransformation (Drug Metabolism) 1. BIOTRANSFORMATION Dr.RENJU.S.RAVI MD 2. OVERVIEW Definition Consequences Types Phase I/II in detail Enzyme Induction/Inhibition First Pass Metabolism 3. Xenobiotics- substances foreign to body include- Drugs, Processed food, Food additives, Cosmetic products, Environmental pollutants, Agrochemicals ...
Overview: Phase I metabolism . oxidation (via cytochrome P450), reduction, and hydrolysis reactions ; phase I reactions convert a parent drug to more polar (water soluble) active metabolites by unmasking or inserting a polar functional group (-OH, -SH, -NH2) geriatric patients have decreased phase I metabolism
Drug Response With Advancing Age. Aging, Effects on Drug Metabolism and Drug Response – Many drugs have different therapeutic effects as well as potential adverse drug reactions, depending on a person’s age. The very young and the very old often have limited liver function, which affects the ways in which the liver metabolizes drugs, resulting in lower thresholds for toxicity and ...