Follow-Up: So I have this roommate, and she has been on Ritalin for several years. And she's terribly withdrawn and at times very on edge. She has a good, stable job, and no obvious reasons to be so on edge. Her conversation is not consistent and she seems to zone out quite a bit. Time and time again I find myself thinking that it's the drug. I don't know what else to think, and it worries me to see these theories of frustration, withdrawal, and aggravation seeming to exist in this person.