l-DOPA, also known as levodopa and l-3,4-dihydroxyphenylalanine, is an amino acid that is made and used as part of the normal biology of humans, as well as some animals and plants. Humans, as well as a portion of the other animals that utilize l-DOPA in their biology, make it via biosynthesis from the amino acid l-tyrosine. [Source: Wikipedia ]