Taking dxm while coming down with adderall?

despite the horrible incidents ive told my friend about with dxm, she still wants to use it recreationally, but not that often. (plz dont tell me that dxm is bad, i already know it is and it won't help this question.) she's been recently prescribed adderall and i want to know if its safe if she took adderall about 9 or so hrs before she took dxm?