Hi! I am new here but decided to jump in.

I just started Effexor in October and am up to 75mg too. The side effects to subside. I also take 40mg of Adderall XR plus 10 mg of Ritalin in the afternoon (if I remember!).
I have not noticed any problems with this combination personally. Everyone is wired differently, so just be aware of how you are feeling. You will be the best judge.