Even if used almost every day, if one were to hypothetically stay in a dosage range of 10-15mg MAX of dex/adderall a day to simply treat ADD, and took all the proper supplements to prevent neurotoxicity, and proper NMDA antagonists such as Magnesium and Zinc to prevent tolerance from increasing, how can this be harmful?
It's the people taking more than 20mg of dexedrine/adderall a day that are setting themselves up for failure. ADD medications should only be used to bring your prefrontal cortex DA levels to "normal transmitting" levels; basically, these should only be used to make focus normal, not provide you with forced motivation. These drugs are supposed to regulate focus, the rest is up to you.
A lot of ADD people are prescribed an abusive dosage of amphetamine, since they are using it to force themselves to do things they don't want to do.
I know I probably offended a lot of people with this post, and I meant no offense, it's just that so many non-drug addicts take tiny doses of amp that it's unfair to make assumptions about amps in general. I have to say I agree with everything written in this thread, though, and want to say this: using it for productivity and cramming schoolwork is where problems appear, using it to make your ADD brain function on an average (non-productive) level is not harmful.
Relying on a dopamine boost to artificially increase your productivity is the real problem, so whether you get that motivation from opiates or amphetamines makes no difference.
Minimal doses of non-methamphetamines are not neurotoxic, and not addictive; the ones who are abusing it are tainting its reputation.