Prior to my basic I was quite heavily addicted to caffeine. I used to drink the equivalent of 8-10 cups of coffee a day. It was not uncommon for me to drink a pot of coffee by myself. I mention this because once first day of basic came along, that came to a screeching halt. You'd think I'd be a mess, but I was ok. I had headaches, but so what, basic isn't supposed to be comfortable. I also had problems staying awake like everyone else, but I struggled through, like everyone else (well, almost everyone). I drank coffee with every meal, and when in the field, some of my buddies would give me the instant coffee packets they didn't want. I drew the line at pills though. Some might disagree, but to me popping pills to stay awake is a slippery slope. It's too easy to pop one a day, then 2, then 10, and so on, but I can only drink so much coffee/coke. What's to stop a desperately addicted caffeine pill addict from going from 10-15 pills of caffeine to speed?
My advice is to stick to caffeinated drinks (ones that don't make you throw up), or nothing. If a heavily addicted caffeine addict can make it through basic on a couple of cups of coffee a day, a 'normal' person should be able to as well. BTW, basic broke my caffeine addiction, and I drink 1-2 cups a day now on average.