What is 3-O-methyldopa (3-OMD)

One of the key substances, or metabolites, that result from the metabolism of LEVODOPA by CATECHOL-O-METHYLTRANSFERASE (COMT). 3-OMD cannot cross the blood-brain barrier, so preventing its formation increases the amount of levodopa that can enter the brain to be converted to dopamine in dopaminergic neurons. comt-inhibitor drugs used to treat Parkinson’s disease can block 3-OMD production, making more levodopa available for conversion to dopamine. See also wEaring-off state.