It is my purpose in this paper to call attention to some of the peculiar drug reactions occurring in man and, at the same time, to offer an explanation of them.
In a perusal of the recent textbooks on pharmacology, it was found that the word "idiosyncrasy" appears in all; but the definitions are almost as numerous as the books themselves, and in none is there any explanation for the peculiar effects of many drugs on certain people.
Given a normal person, any drug exhibited in therapeutic doses manifests a certain normal action, a side action and, in larger amounts, a toxic action, both the normal and the toxic action being more or less definitely fixed, symptomatically, for all individuals of the same species.
On the other hand, there are individuals within any species that manifest exaggerated normal and side actions from many such reasons as alterations in rate of