when l-tryptophan or 5-hydroxytryptophan is administered with phenelzine ( a monoamine oxidase inhibitor ) and carbidopa ( a selective peripheral l-amino acid decarboxylase inhibitor ) to raise brain serotonin , a significant increase in myocardial electrical stability is observed .
C0041249
l-tryptophan
C0000578
5-hydroxytryptophan