Chapter 2, Episode 7: What is Hemicrania Continua and Paroxysmal Hemicrania?


This content has been medically reviewed by Dr. Sarah Bobker.

Paroxysmal hemicrania and hemicrania continua are two types of trigeminal autonomic cephalgias. Trigeminal autonomic cephalgias are a group of primary headache disorders characterized by one-sided head pain and cranial autonomic symptoms. Cranial autonomic symptoms include tearing or redness of the eye, constriction of the eye, drooping or swelling of the eyelid, nasal congestion or runny nose, ear fullness, facial sweating or flushing.

“Paroxysmal” means “sudden attack” and “continua” means “continuous”. “Hemicrania” refers to “one side of the head”. 

According to the International Classification of Headache Disorders, paroxysmal hemicrania is characterized by attacks of severe, one-sided pain around or above the eye, or in the temporal region of the head, lasting 2 to 30 minutes, occurring 5 or more times per day. 

The criteria also states that at least 20 attacks must be experienced to make this diagnosis, and that attacks are accompanied by either:

Restlessness or agitation


At least one cranial autonomic symptom occurring on the same side as the pain.

Episodic paroxysmal hemicrania is when someone experiences at least 2 bouts of attacks that last from 7 days up to 1 year and are separated by pain free periods of 3 months or greater. 

Chronic paroxysmal hemicrania is when periods of relief are less than 3 months in a 1 -year span or there are no symptom-free periods at all. Chronic paroxysmal hemicrania is more common.

Now let’s discuss hemicrania continua.

Hemicrania continua is a persistent or continuous one-sided headache that is present for 3 months or greater with attacks of moderate or severe intensity. 

According to this diagnostic criteria, there must also be the presence of either:

Restlessness or agitation OR aggravation of the pain with movement


At least one cranial autonomic symptom that occurs on the same side as the head pain.

Hemicrania continua can be classified as remitting or unremitting. Remitting hemicrania continua means there are spontaneous pain-free periods of at least 24 hours without treatment. Unremitting hemicrania continua is defined as continuous pain for 1 year with any pain-free periods being less than 24 hours. Unremitting hemicrania continua is more common.

It is very important to note, the final diagnostic criterion of both paroxysmal hemicrania and hemicrania continua is that they respond to the nonsteroidal anti-inflammatory drug  indomethacin. Response to indomethacin is one of the ways these two disorders may be differentiated from the other trigeminal autonomic cephalgias.

Relief is generally quite fast. Indomethacin should be tapered occasionally, typically after 6 months, to determine if remission has occurred.

If Indomethacin cannot be tolerated, there are other medications and treatments that may be helpful. For example, non-invasive vagus nerve stimulation is FDA cleared for the treatment of paroxysmal hemicrania and hemicrania continua. 

Other secondary headache conditions should be excluded by neuroimaging and relevant lab work, prior to diagnosis.

To learn more about these conditions, visit and

*The contents of this video are intended for general informational purposes only and does not constitute professional medical advice, diagnosis, or treatment. Always seek the advice of a physician or other qualified health provider with any questions you may have regarding a medical condition. AMD does not recommend or endorse any treatment, products, or procedures mentioned. Reliance on any information provided by this content is solely at your own risk.