L-DOPA

L-DOPA (L-3,4-dihydroxyphenylalanine; Levodopa; Sinemet, Parcopa, Atamet, Stalevo, Madopar, Prolopa, etc) is a naturally-occurring dietary supplement and psychoactive drug found in certain kinds of food and herbs (e.g., Mucuna pruriens, or velvet bean), and is synthesized from the essential amino acids L-phenylalanine (PHE) and L-tyrosine (TYR) in the mammalian body and brain. L-DOPA is the precursor to the neurotransmitters dopamine, norepinephrine (noradrenaline), and epinephrine (adrenaline) collectively known as catecholamines. Aside from its natural and essential biological role, L-DOPA is also used in the clinical treatment of Parkinson's disease (PD) and dopamine-responsive dystonia (DRD).