What is caffeine?
Caffeine is a stimulant drug found in tea as well as in many other natural substances. Coffee is better known as a dietary source of caffeine (and the source of the name ‘caffeine’), but tea contains a significant amount of the drug. Other natural sources of caffeine are chocolate and yerba maté, which is used as an herbal drink in parts of South America. Caffeine is also added to many foods and drugs, including soft drinks and pain relievers such as Excedrin.
Caffeine is an organic chemical and stimulant drug, used world wide. Pharmacologically, caffeine is one of a group of stimulants called methylxanthines, or xanthines, that occur naturally in some plants. In addition to mental stimulation and sharpening of motor skills, it also acts as a diuretic, removing water from the body via the kidneys; stimulates increased peristalsis in the bowel, prompting evacuation; is a potent vasoconstrictor, raising the blood pressure. All natural sources of caffeine were discovered and used in their native environments from ancient times. The buying and selling of caffeine-bearing products has been an historical stimulus to trade and caffeine remains one of the world’s most popular drugs. Beverages made from the nuts, seeds or leaves of these plants are currently major sources of natural caffeine. These include coffee, made from the seeds of the Coffea arabica plant; soft drinks, like Coca Cola, made from Kola nuts; tea made from the leaves of Thea/camell
