ABSTRACT
Calcitonin gene-related peptide (CGRP) is the m ost pow erful o f the vasodilator transm itters and as one o f the neuropeptides to be found in trigem inal neurons ,1 m ay play a role in the physiology and pathophysiol ogy o f the m igraine and cluster headache .2 In this chapter the evidence for such a role and the physiological im plications tha t m ay be gleaned from the putative involvem ent o f CGRP in p rim ary headache is reviewed.
