Many people think of the word “drug” as meaning a habit-forming sum stance 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, comes from the coca 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 animals also provide useful drugs for man? The thyroid gland, the adrenal glands, and the pancreas produce substances that are made into medicine.

Still another kind of drug are the vaccines, toxoids, and antitoxins. A vaccine contains dead or weakened disease germs. When put into the body, antibodies are created which circulate in the blood stream and protect against that specific disease. A toxoid works in the same way, except that it contains inactive poisons made by disease germs. An antitoxin contains large amounts of antibodies, and it is used to help the body fight infections.

With the development of science, we have been able to make synthetic drugs. These originate, not in plants or animals, but in the laboratories of the research chemist. More and more of our drugs are synthetic, since they can be produced cheaply and in great quantities. Probably the best known synthetic drug is aspirin.

Recently science has made another discovery in the field of drugs — antibiotics. These are chemicals which are produced by molds. The chemicals have the power to stop the growth of many disease-causing bacteria. Penicillin and streptomycin are two important antibiotics.