I've had chemo for brain cancer and it was one drug that they also use on breast cancer (temodar/temozolamide). Now, I was on a really low dose so I felt okay while I was on it, but a few months later I got "chemo brain" which was basically this really hardcore brain fog and I couldn't figure out what to do about it. My neurologist put me on Provigil and that really helped. You may not have that problem, but in case you do, now you know there's something to try.
Good luck!
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What on earth do you think you are, if not a robot, albeit a very complicated one? - Richard Dawkins, The Selfish Gene