2) Stay hydrated. This will keep you alert. If your cells have enough water, your brain will function efficiently even under pressure. With saying that, don't be addictive to caffeine just to keep yourself alert and awake. A cup of expresso is enough to keep you up for the day until the time your body needs to sleep.
3) Take cat naps. Taking 15 to 20 minutes will make you feel energised and rejuvenated. You don't have to schedule this. If you feel like
taking a nap, do so. But be sure to inform your boss and co-workers about it.
4) Skip the sugar. When you're sleep deprived, you're more likely to crave for sugary and salty food. Be determined to avoid them because they will make you feel lazy and sleepy after all. Bring celery sticks, bananas, nuts and other healthy stuff to munch on while you're working. You'll be surprised at how they can make you alert all through out the day.
5) Get out. Ask permission to leave your workstation so you can clear your mind a bit and breathe in some fresh air. Do the same if you're at home doing some chores. This will keep you from loosing it especially when you're faced against a stressful situation.