Many people think of the word "drug" as meaning a habit-forming substance that is taken to relieve pain or to produce sleep. Actually, a drug is any substance or mixture of substances used as a medicine.
The mixing of such substances, the art of healing with "drugs", is a very ancient one. In fact, the first step forward in the treatment of diseases came about through the knowledge that priests and teachers had of plant products and their healing power. The ancient Greeks used plant products as drugs thousands of years ago.
Today, many of our important drugs still come from plants. Morphine and opium are made from the juice of the poppy. Cocaine, which is used to deaden the nerves for operations, come from the cocoa plant.
Quinine is extracted from a bark called "cinchona". Castor oil comes from castor beans.
Many of the important drugs we use today come from minerals, and these include salts, bromides, and phosphorus. Did you know that the organs of