Medication
Introduction
Medication, also known as medicine, pharmaceutical drug, or simply drug, is a substance used to diagnose, cure, treat, or prevent disease. Medication therapy is a crucial part of the medical field and relies on the science of pharmacology for continual advancement and on pharmacy for appropriate management.
Drug Nomenclature
Each medication has unique names: a chemical name, a generic name, and a brand name. The chemical name describes the atomic or molecular structure of the drug. The generic name is derived from the chemical name according to a specific set of rules. The brand name is chosen by the manufacturer, usually on the basis that it can be recognized, pronounced and remembered by health professionals and members of the public.
Classes of Medications
Medications can be classified in various ways, such as by chemical properties, mode or route of administration, biological system affected, or therapeutic effects. An elaborate and widely used classification system is the Anatomical Therapeutic Chemical (ATC) Classification System.
Drug Discovery and Development
Drug discovery is the process by which potential drugs are discovered or designed. In the past, most drugs have been discovered either by isolating the active ingredient from traditional remedies or by serendipitous discovery. Modern biotechnology often focuses on understanding the metabolic pathways related to a disease state or pathogen, and manipulating these pathways using molecular biology or bioinformatics.
Drug development is the process of bringing a new pharmaceutical drug to the market once a lead compound has been identified through the process of drug discovery. It includes pre-clinical research (microorganisms/animals) and clinical trials (on humans) and may include the step of obtaining regulatory approval to market the drug.
Administration
Medication can be administered via many routes, and they can be classified into enteral (passing through the gut), parenteral (outside the gut), and topical (applied to a localized area of the body). Each route has specific purposes, advantages, and disadvantages.
Pharmacokinetics
Pharmacokinetics describes the effect of the body on the administered medications. It includes absorption, distribution, metabolism, and excretion of drugs. It is important to understand these processes to determine how long it takes for a drug to be eliminated from the body, what the best route in the body to administer a drug is, and how to avoid drug interactions.
Pharmacodynamics
Pharmacodynamics describes the effect of the drugs on the body. It includes the therapeutic effect, which is the desired result of therapy, and the side effects, which are the undesired effects of the therapy.
Adverse Drug Reaction and Drug Interaction
An adverse drug reaction (ADR) is an injury caused by taking medication. ADRs may occur following a single dose or prolonged administration of a drug or result from the combination of two or more drugs. A drug interaction is a situation in which a substance affects the activity of a drug when both are administered together.
Medication Compliance and Adherence
Medication compliance (also adherence, or capitation) is the degree to which a patient correctly follows medical advice about taking medications. The World Health Organization estimates that half of all patients fail to take their medications as directed.