The thin line which divides medicine from poison is a nebulous topic- but to break ground I will briefly discuss the act of purging for the purpose of cleansing/healing/transformation. Variations of this process have been used by numerous cultures throughout the ages, and are still in practice today (for example, ayahuasca ceremonies).
The motion/sensation of vomiting is so violent- that horrible feeling which passes near the heart, abrupt, involuntary- as though our entrails are being ripped through the throat.  It can be terrifying or simply unpleasant, but if occurring within the context of healing ritual, this physical storm can be taken deep into the mind, and the nature of what is expelled may involve even the soul.  Instead of scrubbing away at our skin (the barrier, interface)- our innards, heart and soul are wretched up and (potentially) purified.
Given our day to day life permeated by innumerable ‘toxins’ and the culture of fear which surrounds them, it is no wonder there is such a profitable industry around items which cleanse from the inside out.  Some may work (if they work) less violently then a purgative- but without some token sickness, it may be difficult to judge efficacy, among other things… which brings me to the my main point- healing by peace vs. healing by poison… which would you prefer?

  Sculpture by Beth Caveneer Stichter