Stay far far away from caffein or any of those other things that "temporarily restore mental alertness or wakefullness" lol
Sleep as long as you can before the drive, and don't take too many breaks. If you can stop somewhere half way for a light sit down meal (heavy meals will make you tired) it'd be a good idea. Water only, and bring some fruit with you for long lasting sugar energy.
I drove across Canada from Calgary, AB to Hamilton, ON last winter and we did it in one night. Was about 35 hours of driving with a 6 hour break for sleep. I also worked a lot of night shifts and did a study of the effects of night shifts on the human body.
As it gets dark your body will be trying to put you to sleep, just keep your mind occupied and you'll blast right through it. That said there's nothing wrong with a power nap for 30 mins at 2:00 am so help you push through. Are you snowboarding or anything the day you get there? You're probably going to be wigged out for a few hours after the drive lol