The replies on this thread are very surprising... It seems everyone has tried them!!
The question you should ask yourself is why you would need to take pills to alter your normal brain function in the first place? Do you really need to be more focused / more relaxed? Where does the urge of being more productive come from? What is your end goal? Is that goal really going to make you happier?
A huge percentage of the population drinks coffee and alcohol, so it's not that radical. And not everyone's normal is optimal. I have pretty severe ADHD and would kill for medication.
The question you should ask yourself is why you would need to take pills to alter your normal brain function in the first place? Do you really need to be more focused / more relaxed? Where does the urge of being more productive come from? What is your end goal? Is that goal really going to make you happier?