Cluster headaches derive their name from the fact that they occur daily for a period of one to several months. It is rarely noted that these cluster periods occur in many patients at the same time. We do not see any cluster patients for several months and then, we see them daily for a couple of months and now is such a period. It is not clear what environmental factors may be playing a role. These periods when cluster patients start having their attacks do not appear to be related to barometric pressure changes, high allergy seasons, pollution, or any other factors. In some patients attacks occur always in the same season and even the same month, but in many a cluster period can start at any time.
Cluster headaches often cause extremely severe pain, which is always on one side and rarely switch sides from one cluster period to the next. The pain is accompanied by nasal congestion, runny nose and tearing on the side of the headache. Unlike migraine patients who prefer to lie down in a dark and quiet place and not move, patients with cluster headaches become agitated and cannot sit still. The attacks occur once or several times a day, often at the same time of day or night and last anywhere from 15 minutes to a couple of hours. Cluster headaches occur at least twice as often in men than in women and this is probably why cluster headaches are often misdiagnosed in women.
A recent review confirmed that cluster headaches respond well to inhalation of oxygen. The only FDA-approved treatment for the treatment of cluster headaches is injection of sumatriptan to treat each attack. To stop the entire cluster we give occipital nerve blocks and prescribe short courses of prednisone (corticosteroid). If headaches persist, a blood pressure medication, verapamil can be effective if given in high doses. The new migraine drugs, CGRP monoclonal antibodies (Aimovig, Ajovy, and Emgality), appear to be very effective for some patients with cluster headaches, although they are not yet FDA-approved for this type of headaches.
