Meth can be neuroprotective at low doses and is available by prescription for ADHD and obesity. Though, I treat my ADHD with dextroamph and I don't think I need to experience meth (I've heard it is more prone to addiction).
Vast majority of illicit adhd/Adderall on the street is actually just lower dosed meth.
You probably would never know the difference, and many people don't.
A lot of sold-as pure isomers are also simply racemic. People often won't notice that either (due to placebo and other factors), but they won't be getting the full benefit they wanted.
There are outliers like myself of course that cannot have levoamphetamine, it completely disables me. I do not know why and I don't really care to find out. The one and only time I took regular adderall, I had to sleep it off.
