Headache caused immediately, or after a delay, by acute exposure to calcitonin gene-related peptide (CGRP). It resolves spontaneously.
Calcitonin gene-related peptide (CGRP), administered by infusion, causes an immediate headache. It can also cause a delayed headache in people with 1. Migraine, on average 5-6 hours after exposure, which fulfils the diagnostic criteria for 1.1 Migraine without aura.
An increasing number of CGRP-receptor antagonists have been found effective in the acute treatment of migraine.