Working on a bunch of paperwork tonight so just a quickie - Ritalin.
Methylphenidate/Ritalin is probably the best-known ADD drug. It's just another phenethylamine - the broad class of drugs which includes pseudoephedrine, amphetamine, and MDMA. Another phenethylamine that is used in the treatment of ADD is simple amphetamine, which is sold as Adderall.
More like this
A diverse series of compounds, known as the phenethylamines, are created from the amino acid tyrosine (bold, at bottom, below). In vivo, things like adrenaline and dopamine are generated. Small amounts of tyramine are also generated.
I love the apparent paradox of treating ADD/ADHD with a stimulant. You'd think it would make people explode with activity or something.
I believe ritalin selectively stimulates the concentration center of the brain.