Casein is a milk protein with multiple roles in a novel drug delivery system that affects postprandial amino acid delivery in different ways through its intragastric coagulation properties.

Zamicastat is an inhibitor of dopamine β-hydroxylase (DBH).

p-Ethynylphenylalanine (4-Ethynyl-L-phenylalanine), a selective, effective, and reversible tryptophan hydroxylase (TPH) inhibitor, exhibits competitive inhibition with a Ki of 32.6 μM.