ABSTRACT
A number of factors stimulated renewed scientific interest in cannabis sativa after many years of relative neglect. Certainly a concern over the increase in the use of cannabis by young people in most Western countries is important. Cannabis sativa is one of man’s oldest cultivated plants. The general term, cannabis, refers to a variety of preparations derived from the herbaceous plant cannabis sativa. Unfortunately for the cannabis user and the scientist, cannabis sativa may vary more than most plants. It is an extremely adaptable plant, showing great genetic plasticity and susceptibility to environmentally induced changes. Cannabis contains a great array of organic chemicals. Current interest has centered on its unique constituents called cannabinoids. The variable chemical composition of cannabis presents a serious problem in making general statements about many of the characteristics of cannabis dependence. There is much to suggest that most American experience is based on the widespread but relatively infrequent use of an exceedingly weak form of cannabis.
