One of the world's most extensively utilized drugs is caffeine. Pharmacologically, caffeine is one of a category of stimulants known as methylxanthine, or xanthine that is present naturally in a number of plants. Beverages prepared from the nuts, seeds or leaves of these plants are chief sources of natural caffeine, for example coffee, prepared from the Coffea Arabica plant. The alkaloid caffeine is the chief physiologically active substance in coffee and is also known as guaranine or methyltheobromine which works as a mild stimulant. Caffeine is a substance that is found naturally in the leaves, seeds or fruits of over 60 plants, together with coffee and cocoa beans, cola nuts and tea leaves. These are employed to produce beverages for example coffee, tea and cola drinks, and foods for instance chocolate.
One widespread source of caffeine is the coffee plant, the beans of which are utilized to prepare coffee. The content of caffeine differs considerably between Arabica and Robusta species and to a slighter extent between types of each species
Caffeine stimulates the central nervous system, having the impact of preventing tiredness and bringing back attentiveness. Beverages containing caffeine, for example coffee, is extremely popular making caffeine the world's most accepted psychoactive substance with an accompanying apprehension for caffeine addiction as well as caffeine withdrawal.
Extreme caffeine ingestion can give rise to harmful caffeine effects including rapid heart rate, diuresis or excessive urination, sickness and vomiting, restiveness, nervousness, dejection, tremors, and sleeplessness.