Pharmacophore Modeling Approach to Antibacterial Drug Discovery

A substance used in the diagnosis, treatment, or prevention of a disease or as a component of a medication. Such a substance as recognized or defined by the U.S. Food, Drug, and Cosmetic act". Drugs are generally defined as molecules which affect biological processes. In order to be effective, the molecule must be present in the body at an adequate concentration for it to act at the specific site in the body where it can exert its effect. Additionally, the molecule must be safe that is, metabolized and eliminated from the body without causing injury. A drug, broadly speaking, is any substance that, when absorbed into the body of a living organism, alters normal bodily function. There is no single, precise definition, as there are different meanings in drug control law, government regulations, medicine, and colloquial usage. In pharmacology, a drug is "a chemical substance used in the treatment, cure, prevention, or diagnosis of disease or used to otherwise enhance physical or mental well-being." Drugs may be prescribed for a limited duration, or on a regular basis for chronic disorders.