Possible Interaction: Carbidopa and Tryptophan

“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.”

“These measures were made on two drug-free baseline days and on two days when the subjects had been receiving the peripheral decarboxylase inhibitor, carbidopa , which inhibits tryptophan metabolism via extracerebral indoleamine pathways.”

“2) In hepatocytes incubated with a low physiological concentration (0.1 mM) of tryptophan, carbidopa (5 × 10 −5 M) produced a significant inhibiton of kynureninase activity.”