Is Cannabis Safe?

Abstract The results of safety studies in animals have been negative. There are very few human cases of cannabis-related death, and these are probably related to other factors. This chapter discusses whether teenage cannabis use leads to subsequent psychotic illness. It also discusses the difficulty of proving cause and effect. Effects of cannabis on motivation and driving are considered. The teenage brain may be especially vulnerable. Tolerance and dependence are real. The special hazards of smoked cannabis are examined, as is whether cannabis is a “gateway drug.” Finally, the chapter discusses whether there any effects persist after cessation of cannabis use.