klara makes a good point. As convenient as caffeine seems in the moment, it is deadly to your health and in the end makes you more tired than you were initially.
if you wanted some quick reading:
http://www.webmd.com/mental-health/n...for-your-heart
http://www.newstarget.com/012352.html
I would suggest to slowly slip off caffeine and alter your diet and lifestyle to provide you with enough energy as not to be dependent on it.