Nootropics are smart drugs. They can help with focus and attention, or simply serve as a weak stimulant - not unlike coffee. I started using them out of curiosity and they grew on me as an extra tool to help with concentration.
There are a variety of Nootropics out there, and I have only tried but the combination, stack, of Noopept and Citicoline, as per suggested by a friend back in Tokyo. I order my supplements from Intellimeds, shipping to Canada. I take this stack every day for a sequence of 30 days, then stop for a week as it seems to make the effect stronger when I start again at the end of the week.
It feels a bit like coffee, but with a light tunnel vision, the immediate effect is that of tuning out the voices in your head for a moment. When cycling on Noopept, it feels a bit like seeing wider. When coding, it feels a bit like things need to get done. I have been taking it for more than a year and I have yet to feel any negative effect. Noopept can be distracting at times, I heard that Racetams are weaker and might be more what you are looking for - I have yet to try them.