Caffeine is a stimulant that is used to stay awake and it gives mental alertness from fatigue. This is used as an adjunct for pain relief and also as energy accelerates. Caffeine is a non-prescription drug easily available as over the counter medication and comes in combination to acquire relief from headache and pain. Caffeine increases the mental alertness by offering the required energy for exercise training and weight loss. Caffeine cannot be considered as a mere stimulant as it reaches deep into muscles and provides power that is long lasting. Caffeine taken before any work out is also great as it fights the fatigue and keeps the person ready for the workout. Dieters also find caffeine as the solution as they feel sluggish. This is a no-calorie stimulant and does its job effectively and quickly. Caffeine anhydrous is found even in one or two coffee cups. However, this limitation is recommended as excess caffeine may result in irritability, rapid heart beat, nervousness and sleeplessness.