Oh, the possible negatives I had in mind were brain-related: "diminishing returns" due to tolerance or other factors after long-term use, and adverse side-effects of the drug flooding your brain with seratonin and dopamine over long periods of time (obviously similar to that observed in long-term methamphetamine use).

I see. I wasn't a long-term user and was always extremely conservative with my dosage, so I didn't encounter any of those brain-related issues.

Even with the fact that they are in the same family of drugs, comparisons to long-term meth abusers doesn't seem quite right.

Every person is different, and meth is definitely abused in higher proportions more than prescription adderall — I am not contesting that, or attempting to compare adderall users to meth users.

I am trying to highlight the similarities between the drugs themselves.