Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
The large neutral amino acids tryptophan, phenylalanine, and tyrosine, which are absorbed in the intestine [20], are precursors of monoamines. Tryptophan and phenylalanine are essential amino acids, meaning that they cannot be synthesized by the human body itself [21]. 5-HTP = 5-Hydroxytryptophan.
