An antagonism between 3-4 dioxyphenylalanine (DOPA) and 5-hydroxytryptophan (5-HTP).
D006916:5-Hydroxytryptophan; D004295:Dihydroxyphenylalanine / Q000494:pharmacology*; D014364:Tryptophan / Q000031:analogs & derivatives
D004295:Dihydroxyphenylalanine; D014364:Tryptophan; D006916:5-Hydroxytryptophan
DOPA/pharmacology; TRYPTOPHAN/related compounds