The varied aspects of drugs, their source, abuse, chemical composition, and physical, personal, and social effects are explored. Seven units cover the following areas: (1) an overview on drug use, a brief history of drugs and discussion of social implications; (2) the human nervous system and the actions of drugs; (3) "nondrug drugs" such as alcohol, nicotine, caffeine, and overthecounter drugs; (4) the use and misuse of psychotherapeutic drugs; (5) the narcotic drugs; (6) the phantasticants; and (7) conclusions and discussion of drug use in modern society. (JD)