Biochemical and physiological approaches to opiate dependence.

Biochemical and physiological theories of opiate addiction are reviewed in an historical context. The biochemical evidence implicating acetylcholine and norepinephrine in the phenomena of tolerance and physical dependence is described, and the six major biochemical and physiological theories are reviewed, emphasizing their close ties (differing sometimes only linguistically) with late nineteenth century theories of tolerance and physical dependence. The operational-reductionistic approaches taken by these theorists, especially when defining psychic dependence, is criticized from a phenomenological point of view while also emphasizing that characteristics of the social structure and moral viewpoints must also be taken into account when studying these phenomena.