Search results
Results From The WOW.Com Content Network
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 biochemistry, such as any drug ...
Distribution is defined as the reversible transfer of a drug between one compartment to another. Some factors affecting drug distribution include regional blood flow rates, molecular size, polarity and binding to serum proteins, forming a complex. Distribution can be a serious problem at some natural barriers like the blood–brain barrier.
In reality, there are many factors affecting this goal. Pharmacokinetic factors determine peak concentrations, and concentrations cannot be maintained with absolute consistency because of metabolic breakdown and excretory clearance. Genetic factors may exist which would alter metabolism or drug action itself, and a patient's immediate status ...
An example of a drug where first-pass metabolism is a complication and disadvantage is in the antiviral drug remdesivir. Remdesivir cannot be administered orally because the entire dose would be trapped in the liver with little achieving systemic circulation or reaching target organs and cells (for example, cells infected with SARS-CoV-2).
Whether a drug is taken with or without food will also affect absorption, other drugs taken concurrently may alter absorption and first-pass metabolism, intestinal motility alters the dissolution of the drug and may affect the degree of chemical degradation of the drug by intestinal microflora.
A drug's removal rate will be determined by the proportion of the drug that is removed from circulation by each organ once the drug has been delivered to the organ by the circulating blood supply. [1] This new concept builds on earlier ideas and it depends on a number of distinct factors: The drugs characteristics, including its pKa.
In terms of drug-drug interactions, acetaminophen activates CAR, a nuclear receptor involved in the production of metabolic enzymes, which increases the metabolism of other drugs. This could either cause reactive intermediates/drug activity to persist for longer than necessary, or the drug will be cleared quicker than normal and prevent any ...
Enzyme induction is a process in which a molecule (e.g. a drug) induces (i.e. initiates or enhances) the expression of an enzyme. Enzyme inhibition can refer to the inhibition of the expression of the enzyme by another molecule; interference at the enzyme-level, basically with how the enzyme works.