Hemicrania continua is a rare but treatable primary headache disorder, meaning that it’s not caused by another condition. The name hemicrania continua describes the hallmark features of this headache:
- Hemicrania means one-side of the head (unilateral or side-locked)
- Continua means continuous
Thus, as the name implies, hemicrania continua is a one-sided headache that is daily and continuous. Along with the daily, one-sided headache, it also causes exacerbations of more severe headache on the same side as the daily headache that can be associated with a sense of restlessness or agitation (not wanting to stay still or preferring to pace or move). Hemicrania continua is also associated with episodes of redness or tearing of the eye, runny or stuffy nose, sweating or flushing of the face on the same side of the headache (called unilateral cranial autonomic symptoms). In addition, hemicrania continua resolves completely with taking indomethacin (a medicine in the NSAID family) and this exquisite responsiveness to indomethacin is required to make the diagnosis. Ice-pick pain may also be seen in patients with hemicrania continua.
People suspected of having hemicrania continua should be carefully assessed by their doctor for an underlying cause, including getting images of the brain. As well, they should be evaluated to make sure that they do not have a different primary headache disorder that can mimic hemicrania cotninua. Other primary headache disorders that mimic hemicrania continua include cluster headache and chronic migraine.
Please refer to the International Classification of Headache Disorders 3rd edition (beta version) website for more information on the criteria used to diagnosis hemicrania continua: https://www.ichd-3.org/3-trigeminal-autonomic-cephalalgias/3-4-hemicrania-continua/
Indomethacin is the treatment of choice for hemicrania continua. If people cannot take indomethacin, there are case reports of gabapentin, melatonin, topiramate, verapamil, onabotulinumtoxinA and occipital nerve stimulation for treatment of hemicrania continua.
The cause of hemicrania continua is unknown. As with migraine disease and many other headache disorders, there is no definitive diagnostic test for hemicrania continua. When a person has symptoms of hemicrania continua, a trial of indomethacin may confirm the diagnosis. However, even people fitting all criteria for hemicrania continua, including a complete response to indomethacin, can have a secondary etiology. Tests such as imaging of the brain may be performed to rule out other causes for the headache.
The International Headache Society. https://www.ichd-3.org/3-trigeminal-autonomic-cephalalgias/3-4-hemicrania-continua/
Tepper D. Hemicrania continua. Headache 2015;55:919-920.
VanderPluym J. Indomethacin-responsive headaches. Curr Neurol Neurosci Rep 2015;15:516-014-0516-y.