Do you mean Ritalin (Methylphenidate) or Dextroamphetamine? (Both prescribed for ADHD). Either way, that statement is not strictly correct. Dextroamphetamine does get metabolised into Methamphetamine, but it isn't Methamphetamine when it is sold & Methylphenidate is something different.
Dextromethamphetamine (Desoxyn). It's the exact same thing as illegal methamphetamine (minus any adulterants of course), but street meth can also be a racemic mixture.
