EDN1 and migraine disorder: The CHM formula CXCTS was proven more effective for migraine compared to flunarizine, as monotherapy or adjunct treatment, by clinical studies, and its anti-migraine effects was achieved by elevating plasma level of 5-hydroxytryptamine (5-HT) and β-endorphin, as well as down-regulating CGRP, substance P and endothelin-1 in the plasma (Yuan and Tan, 2012; Sun and Xu, 2016; Zhou, 2022).