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Monoamine precursor
From Wikipedia, the free encyclopedia
Monoamine precursors are precursors of monoamines and monoamine neurotransmitters in the body.[1][2] The amino acids L-tryptophan and L-5-hydroxytryptophan (5-HTP; oxitriptan) are precursors of serotonin and melatonin, while the amino acids L-phenylalanine, L-tyrosine, and L-DOPA (levodopa) are precursors of dopamine, epinephrine (adrenaline), and norepinephrine (noradrenaline).[1][2] Administration of monoamine precursors can increase the levels of monoamine neurotransmitters in the body and brain.[2] Monoamine precursors may be used in combination with peripherally selective aromatic L-amino acid decarboxylase inhibitors (AAAD inhibitors; also known as DOPA decarboxylase (DDC) inhibitors) such as carbidopa and benserazide.[3] Carbidopa/levodopa is used to increase brain dopamine levels in the treatment of Parkinson's disease[3] while carbidopa/oxitriptan (EVX-101) is under development as an antidepressant for possible use in the treatment of depression.[4]
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