A drug is defi ned as an agent intended for use
in the diagnosis, mitigation, treatment, cure, or
prevention of disease in humans or in other
animals (Food, Drug, and Cosmetic Act, 1938).
One of the most astounding qualities of drugs is
the diversity of their actions and effects on the
body. This quality enables their selective use in
the treatment of a range of common and rare
conditions involving virtually every body organ,
tissue, and cell.