I don't smoke or consume nicotine usually, but a few times over the past decade or so I have picked up a pack of nicotine gum to help boost focus for long days. I never got addicted and have mostly replaced the practice with a brisk walk for a few blocks. I might have done this like... 5 or 6 times in the past decade.
The one place I would still use it, if I ever find myself in this situation again, is on long trips involving an international flight where after being shot across the ocean I'm expected to show up in a disoriented state in front of customers and work together on something.
