David T. Courtwright 
Forces of Habit [PDF ebook] 
Drugs and the Making of the Modern World

What drives the drug trade, and how has it come to be what it is today? A global history of the acquisition of progressively more potent means of altering ordinary waking consciousness, this book is the first to provide the big picture of the discovery, interchange, and exploitation of the planet’s psychoactive resources, from tea and kola to opiates and amphetamines.