When I was Infantry I used a cocktail of caffeine and nicotine (usually nasal snuff, sometimes supplemented with dipping tobacco) to stay awake on extended miss

When I was Infantry I used a cocktail of caffeine and nicotine (usually nasal snuff, sometimes supplemented with dipping tobacco) to stay awake on extended missions. Since nicotine is a vasoconstrictor it inhibited night vision to some degree, but that was better than nodding off. Now that I'm a professional engineer and no longer in indentured servitude I stick to an 8 hour work day, get 7-8 hours of sleep a night, and have the rest of the day to spend with the family. There's no reason in this day and age to work yourself to the point of chemical dependence if your life isn't on the line.