circannual periodicity

Cluster Headache: Improving Therapy for the Worst Pain Experienced by Humans

Cluster headache is a brain disorder dominated clinically by dreadful episodes of excruciating pain with a circadian pattern and most often focused in bouts with circannual periodicity. As we have understood its neurobiology new therapies, including those directed at calcitonin gene-related peptide, are helpful improve the lives of sufferers.