The term ‘drug’ is difficult to define objectively. This is because what constitutes a ‘drug’ is both a subjective and a socio-cultural construct. It can mean anything from tea to heroin. One definition is that a drug is: “Any substance that people consider to be a drug, with the understanding that this will change from culture to culture, and from time to time” (Krivanek, 1995).
An alternative definition, which includes both substances and behaviours within the category of ‘drug’, is that: “We may consider the objects of addiction to be those things which reliably and robustly shift subjective experience” (Shaffer, 1997).
The World Health Organisation defines a drug as: “Any substance which when taken into the body, alters its function physically and/or psychologically, excluding food, water, and oxygen” (1994).
There seems to be a human need for mood-altering substances. There is evidence that drugs, or mood-altering substances, have always been a part of human culture, since at least the Old Stone Age. Throughout recorded history they have served a sacramental function, a medical function, a celebratory function and a mood-altering function.
Social norms prescribe what is, and is not, approved drug use. Although this has always been the case, these norms change from culture to culture and from era to era, as do the sanctions that society applies to those individuals who do not conform to these norms. One century’s celebrated drug is another generation’s illicit substance