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MEDLINE Indexing Online Training Course

Category D - Chemicals and Drugs

Indexing Principles

Chemicals and Drugs [D]

  • Inorganic Chemicals [D01]
  • Organic Chemicals [D02]
  • Heterocyclic Compounds [D03]
  • Polycyclic Compounds [D04]
  • Macromolecular Substances [D05]
  • Hormones, Hormone Substitutes, and Hormone Antagonists [D06]
  • Enzymes and Coenzymes [D08]
  • Carbohydrates [D09]
  • Lipids [D10]
  • Amino Acids, Peptides, and Proteins [D12]
  • Nucleic Acids, Nucleotides, and Nucleosides [D13]
  • Complex Mixtures [D20]
  • Biological Factors [D23]
  • Biomedical and Dental Materials [D25]
  • Pharmaceutical Preparations [D26]
  • Chemical Actions and Uses [D27]

Category D contains the MeSH terms for drugs and chemicals. In MeSH, the concept of drugs and chemicals is very broad; the terms are often used interchangeably. It includes not only what is commonly known as "therapeutic drugs" (ASPIRIN) and pure chemicals (SODIUM CHLORIDE or ETHYLAMINES), but also a variety of biological substances (ANTIBODIES; AMINO ACIDS; PROTEINS; NUCLEIC ACIDS; VENOMS; PLANT EXTRACTS, etc). It also includes chemicals of environmental or industrial importance (PESTICIDES; PLASTICIZERS). It is the largest MeSH category and is divided into several subcategories. These subcategories group drug and chemical headings by their structure and by their function.

Structural subcategories include: INORGANIC CHEMICALS (D1), ORGANIC CHEMICALS (D2), etc.

Functional subcategories include: CARDIOVASCULAR AGENTS, DERMATOLOGIC AGENTS, etc which are located in subcategory D27 (Chemical Actions and Uses).

Hormones, enzymes, proteins, nucleic acids, carbohydrates, lipids, and other biomolecules are grouped in separate subcategories.

Drug action or activity is defined broadly by the MeSH term PHARMACOLOGIC ACTIONS.

Last Reviewed: March 18, 2016