The primitive pharmacologist

Primitive people at some point, by trial and error, learned that certain herbs mixed in certain ways, were poisonous.  The same way we might feel about a killer, primitive man loathed the poisoner because poison involves the death of a person without the chance to put up a fight.

In Homer's Odyssey the poisoner was referred to as the pharmakos, which means a poisoner, sorcerer or magician.  The origin of the verb the word "drug" is derived from is still debated, and possibly it means one of two things:

1. To give drugs of poisons
2. To drive away evil spirits with blows

Regardless, it probable the "original pharmacologist was eyed with suspicion."  (1, page 24)  To put this into perspective, primitive medicine involved superstition, which was inculcated by the medicine man.  

References:

1. Garrison, Fielding Hudson, "An introduction to the history of medicine," 1920,  Philadelphia, W.B. Saunders Company