When drank in excess, it can cause caffine addictions, liver problems, heart murmors, and high blood pressure. These are the same effects of high amount of any caffine products though.
They contain much stimulant and are cheating people's body.It is said that different kinds of excitant will enlarge their interacttion among each other and cause great danger.If you have them before sporting, they may arouse some heart disease.
I think that there are a lot of dangers in energy drinks because there are full of sugar and the stuff that is really bad for your system. It gives you a lot of eneregy at first and then it makes you really sleepy once it starts to ware off. I do not think that it is good for you.