In a lot of drugs, euphoria is at least partially proportional to the rate of blood level increase, e.g. [1]. [1] http://www.dddmag.com/article/2009/07/questio

In a lot of drugs, euphoria is at least partially proportional to the rate of blood level increase, e.g. [1]. [1] http://www.dddmag.com/article/2009/07/question-opioid-euphoria http://www.dddmag.com/article/2009/07/question-opioid-euphor...