Levodopa (LDP)

L-DOPA (L-3,4-dihydroxyphenylalanine) is a chemical that is made and used as part of the normal biology of humans, some animals and plants. Some animals and humans make it via biosynthesis from the amino acid L-tyrosine. L-DOPA is the precursor to the neurotransmitters dopamine, norepinephrine (noradrenaline), and epinephrine (adrenaline) collectively known as catecholamines. L-DOPA is produced from the amino acid L-tyrosine by the enzyme tyrosine hydroxylase (TH). It is also the precursor for the monoamine or catecholamine neurotransmitters dopamine, norepinephrine (noradrenaline), and epinephrine (adrenaline). Dopamine is formed by the decarboxylation of L-DOPA. L-DOPA can be directly metabolized by catechol-O-methyl transferase (COMT) to 3-O-methyldopa (3-OMD), and then further to vanillactic acid (VLA).