CALCA and migraine disorder: Migraine without Aura (MO) are essentially menstrual migraine and even in this case they do not differ much from the previous ones because they respond well to the same therapies as MA (NSAIDs, Triptans etc.), which means that the basic mechanism is same: vasoconstriction, reactive vasodilation and extravasation, CGRP etc. In these patients, the menstruation, this must be considered, to all intents and purposes, a large wound, with a large production of Prostaglandins and varius inflammation mediators (hence the pain in the lower abdomen).