> Adderall / Vyvanse is prescription meth (something I've heard from several of my AD(H)D friends).
No, that's Desoxyn[0].
What you may be referring to is that Adderall, methamphetamine, and MDMA have remarkably similar effects, which is true - the active ingredients in all three are metabolized in a similar manner, and the main differences are the means of ingestion, the bioavailability, and set/setting. In methamphetamine, for example, the extra methyl group simply ensures that it can cross the blood-brain barrier more easily, but it doesn't change the actual effect of the drug in itself.