This may seem like a serious case of stating the obvious but it goes without saying that the antidote to tiredness is sleep. If you haven’t got time for 8 hours then try taking a short nap instead.
According to Dr David Dinges, editor of the journal SLEEP, a nap a short as 10 minutes can be of benefit to you by moving the brain into slow-wave sleep. According to Dinges, sleeping for longer than 40 minutes could leave you feeling slightly groggy upon waking, but this will soon wear off and you will feel sharper afterwards.
Drink caffeinated beverages
Though this is neither an ideal or long term solution it does do the trick temporarily. The average person needs around 100 – 200 milligrams of caffeine and it will take around 15 to 30 minutes for the effects to kick in. The benefits will last for around three to four hours.
Keep the light on
Bright lights will tend to hurt your eyes when you’re tired because your body clock will think you should be sleeping and it should be dark. This effect tends to result in individuals turning artificial lights off but actually it is better to leave them on. Better still, go outside into the sunshine and get your fix of sunlight.
Walking around will get the blood moving and this in turn will boost your brain power. When you move around your muscles will send feedback to the central mechanism of the brain to improve your alertness.
For more tips view the original WebMD article.