Pharmacology is a branch of medicine, biology, and pharmaceutical sciences concerned with drug or medication action, where a drug may be defined as any artificial, natural, or endogenous molecule which exerts a biochemical or physiological effect on the cell, tissue, organ, or organism. It is the science of drugs including their origin, composition, pharmacokinetics, therapeutic use, and toxicology. More specifically, it is the study of the interactions that occur between a living organism and chemicals that affect normal or abnormal biochemical function. If substances have medicinal properties, they are considered pharmaceuticals.
Drug tolerance or drug insensitivity is a pharmacological concept describing subjects' reduced reaction to a drug following its repeated use. Increasing its dosage may re-amplify the drug's effects; however, this may accelerate tolerance, further reducing the drug's effects. Drug tolerance is indicative of drug use but is not necessarily associated with drug dependence or addiction. The process of tolerance development is reversible and can involve both physiological factors and psychological factors.
In pharmacology, bioavailability is a subcategory of absorption and is the fraction (%) of an administered drug that reaches the systemic circulation.
ADME is an abbreviation in pharmacokinetics and pharmacology for "absorption, distribution, metabolism, and excretion", and describes the disposition of a pharmaceutical compound within an organism. The four criteria all influence the drug levels and kinetics of drug exposure to the tissues and hence influence the performance and pharmacological activity of the compound as a drug. Sometimes, liberation and/or toxicity are also considered, yielding LADME, ADMET, or LADMET.
Cytochrome P450 3A4 is an important enzyme in the body, mainly found in the liver and in the intestine. It oxidizes small foreign organic molecules (xenobiotics), such as toxins or drugs, so that they can be removed from the body. It is highly homologous to CYP3A5, another important CYP3A enzyme.
Drug metabolism is the metabolic breakdown of drugs by living organisms, usually through specialized enzymatic systems. More generally, xenobiotic metabolism 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 or poison. These pathways are a form of biotransformation present in all major groups of organisms and are considered to be of ancient origin. These reactions often act to detoxify poisonous compounds. The study of drug metabolism is called pharmacokinetics.
The first pass effect is a phenomenon of drug metabolism at a specific location in the body which leads to a reduction in the concentration of the active drug, specifically when administered orally, before it reaches the site of action or systemic circulation. It is the fraction of drug lost during the process of absorption which is generally related to the liver and gut wall. The liver is the major site of first pass effect, it can also occur in the lungs, vasculature or other metabolically active tissues in the body. Notable drugs that experience a significant first-pass effect are buprenorphine, chlorpromazine, cimetidine, diazepam, ethanol, imipramine, insulin, lidocaine, midazolam, morphine, pethidine, propranolol, and tetrahydrocannabinol (THC).
Physiologically based pharmacokinetic (PBPK) modeling is a mathematical modeling technique for predicting the absorption, distribution, metabolism and excretion (ADME) of synthetic or natural chemical substances in humans and other animal species. PBPK modeling is used in pharmaceutical research and drug development, and in health risk assessment for cosmetics or general chemicals.
N-acetyltransferase (NAT) is an enzyme that catalyzes the transfer of acetyl groups from acetyl-CoA to arylamines, arylhydroxylamines and arylhydrazines. They have wide specificity for aromatic amines, particularly serotonin, and can also catalyze acetyl transfer between arylamines without CoA. N-acetyltransferases are cytosolic enzymes found in the liver and many tissues of most mammalian species, except the dog and fox, which cannot acetylate xenobiotics.
Pharmacokinetics, sometimes abbreviated as PK, is a branch of pharmacology dedicated to determining the fate of substances administered to a living organism. The substances of interest include any chemical xenobiotic such as: pharmaceutical drugs, pesticides, food additives, cosmetics, etc. It attempts to analyze chemical metabolism and to discover the fate of a chemical from the moment that it is administered up to the point at which it is completely eliminated from the body. Pharmacokinetics is the study of how an organism affects a drug, whereas pharmacodynamics (PD) is the study of how the drug affects the organism. Both together influence dosing, benefit, and adverse effects, as seen in PK/PD models.
The British Journal of Pharmacology is a biweekly peer-reviewed medical journal covering all aspects of experimental pharmacology. It is published for the British Pharmacological Society by Wiley-Blackwell. It was established in 1946 as the British Journal of Pharmacology and Chemotherapy. The journal obtained its current title in 1968.
Benoxaprofen, also known as Benoxaphen, is a chemical compound with the formula C16H12ClNO3. It is a non-steroidal anti-inflammatory drug (NSAID) of the propionic acid class, and was marketed under the brand name Opren in the United Kingdom and Europe by Eli Lilly and Company (commonly referred to as Lilly), and as Oraflex in the United States of America (USA). Lilly suspended sales of Oraflex in 1982 after reports from the British government and the United States Food and Drug Administration (US FDA) of adverse effects and deaths linked to the drug.
Phytotherapy Research is a monthly peer-reviewed scientific journal publishing original research papers, short communications, reviews, and letters on medicinal plant research. Key areas of interest are pharmacology, toxicology, and the clinical applications of herbs and natural products in medicine, from case histories to full clinical trials, including studies of herb-drug interactions and other aspects of the safety of herbal medicines. Papers concerned with the effects of common food ingredients and standardised plant extracts, including commercial products, are particularly relevant, as are mechanistic studies on isolated natural products.
Immunopharmacology and Immunotoxicology is a bimonthly peer-reviewed medical journal that covers preclinical and clinical studies on the regulatory effects of various agents on immunocompetent cells, as well as the immunotoxicity exerted by xenobiotics and drugs. Hence, the journal encompasses a broad range of pathologies. It is published by Informa.
Established in 1972, Drug Metabolism Reviews is an academic journal that publishes review articles on all aspects of drug metabolism research. It is the official journal of the International Society for the Study of Xenobiotics (ISSX).
Biochemical Pharmacology is a peer-reviewed medical journal published by Elsevier. It covers research on the pharmacodynamics and pharmacokinetics of drugs and non-therapeutic xenobiotics. The editor-in-chief is S. J. Enna, University of Kansas Medical Center, Kansas City.
Drug Metabolism and Disposition is a peer-reviewed scientific journal covering the fields of pharmacology and toxicology. It was established in 1973 and is published monthly by the American Society for Pharmacology and Experimental Therapeutics. The journal publishes articles on in vitro and in vivo studies of the metabolism, transport, and disposition of drugs and environmental chemicals, including the expression of drug-metabolizing enzymes and their regulation. As of 2022, the editor-in-chief is XinXin Ding.
In pharmacology the elimination or excretion of a drug is understood to be any one of a number of processes by which a drug is eliminated from an organism either in an unaltered form or modified as a metabolite. The kidney is the main excretory organ although others exist such as the liver, the skin, the lungs or glandular structures, such as the salivary glands and the lacrimal glands. These organs or structures use specific routes to expel a drug from the body, these are termed elimination pathways:
Leon Aarons is an Australian pharmacist who researches and teaches in the areas of pharmacodynamics and pharmacokinetics. He lives in the United Kingdom and from 1976 has been a professor of pharmacometrics at the University of Manchester. In the interest of promoting the effective development of drugs, the main focus of his work is optimizing pharmacological models, the design of clinical studies, and data analysis and interpretation in the field of population pharmacokinetics. From 1985 to 2010 Aarons was an editor emeritus of the Journal of Pharmacokinetics and Pharmacodynamics and is a former executive editor of the British Journal of Clinical Pharmacology.
