I am firstly sorry to hear about your friend. Energy drinks contain caffeine in large amount. Even though occasional use of these energy drinks is ok, it become a problem if it is used in large amount. Secondly, not sleeping and taking too many energy drinks can cause excessive exhaustion, making him predisposed to various illnesses. One doubt i have is , is he having some kind of psychiatric illness or drug abuse
as well. There are lot many issues that can be answered only after examining him. Provided he is in ICU
, i think he should be in good hands and should be out of it soon.