A classification of drug action based on therapeutic effects.

A systematic classification system has been developed for the categorization of therapeutic effects of individual drugs based on their relationships to the underlying disease processes being treated or prevented, rather than on the pharmacologic or biochemical effects of the individual drugs. This system involves a total of six categories of different therapeutic specificities, involving four categories based on disease process-oriented mechanisms of drug action (Categories I through IV), and two additional ones (Categories 0 and V) to complete the classification system. Category 0 includes drugs or drug uses that prevent the development of a disease when none exists; Category I, those that affect etiologic factors of a disease; Category II, those that affect specific disease processes; Category III, those that affect specific disease manifestations; Category IV, those that affect non-specific disease manifestations or symptoms; and Category V includes drug uses or drugs used to diagnose or facilitate treatment of a disease. Examples are provided for each category as well as for applications of the classification system.