The pain from a cluster headache is worse than childbirth, patients say. Worse than kidney stones. More like getting shot in the head or being jabbed in the eye by a sharp object.
Cluster headaches, which occur in clusters, or patterns, tend to follow certain rules, Burish says. Typically, an intense pain is felt on one half of the face, and some features of the headache can be outwardly apparent. On the painful side of the face, the eye may be droopy, bloodshot, swollen, and watery.
One of the newer pieces of Burish’s research relates to the timing and circadian rhythm of cluster headaches. They tend to last three hours or less, and might happen many times per day. In addition, most people with cluster headaches get them the same time every year. Burish would like to do more research on circadian rhythms and cluster headaches, but says it could take five years to collect samples that will help his team. And because cluster headaches are somewhat uncommon, affecting 1 in 1,000 people, gathering data and funding research is challenging.