Caffeine is the most widely used central nervous system stimulant, regularly consumed by 80 percent of adults throughout the world. It is present in coffee, tea, many soft drinks (including colas, Mountain Dew, and Mello Yello), and chocolate. Recently, it has been added to bottled spring water, such as Verifine Fruit2O Plus: Citrus Energy. Caffeine is a component of most beverages marketed as energy drinks, including AMP, Venom, and Adrenaline Rush. Caffeine is also an ingredient of some cold medications, diet pills, headache remedies, pain relievers, allergy tablets, antacids, and sleep prevention compounds.