Energy drinks are soft drinks that have caffeine,taurine, glucuronolactone and other ingredients that are stimulants. For this reason, energy drinks are also known as smart drinks or stimulant drinks. Energy drinks are by definition: beverages, that typically contain caffeine, taurine and vitamin(s), and may contain an energy source (e.g. carbohydrate), and/or other substance(s), used for an enhanced physiological and/or for performance effects. Consumers purchase and consume energy drinks for a many reasons and Primal Energy is the shot and drink available in 2 oz bottles, or 16 oz bottles.