For the lecture record them to take notes later and just listen to the lecture while there. Get to know your professor's and hand in your work at their office, their more accepting of when you have issues if they know you and you ask for help or ask questions in their office. See if your school has a TRIO program, if it's a state school it does. As far as ways to improve your memory lumosity type programs can help. Accept because you are medicated your brain won't be the same, that's kind of the point and this is just a side effect of that, Sorry.