Hemicrania continua is a chronic and persistent form of headache marked by continuous pain that varies in severity and always occurs on the same side of the face and head. Some individuals with hemicrania continua have bilateral pain, or pain on both sides of the head. Most people experience attacks of increased pain three to five times per 24-hour cycle.

A headache is considered hemicrania continua if the person has had a one-sided daily or continuous headache of moderate intensity with occasional short, piercing head pain for more than three months without shifting sides or pain-free periods. The headache must also be completely responsive to treatment with the non-steroidal anti-inflammatory drug (NSAID) indomethacin. It must have at least one of the following symptoms:

Eye redness and/or tearing Nasal congestion and/or runny nose Ptosis (drooping eyelid) Miosis (contracture of the iris) Occasionally, individuals will also have forehead sweating and migraine symptoms, such as:

Throbbing pain Nausea and/or vomiting Sensitivity to light and sound There are two forms of hemicrania continua:

Chronic, with daily headaches Remitting, in which headaches may occur for as long as six months and are followed by a pain-free period of weeks to months until the pain returns Hemicrania continua occurs on its own and is not a symptom of another disorder. It is more common in women than in men and occurs more often in adult women. Physical exertion and alcohol use may increase the severity of headache pain in some people. The cause of this disorder is unknown.

Indomethacin provides rapid relief from symptoms. Some individuals may need to take acid-suppression medicine due to a gastrointestinal side effect. For those who cannot tolerate the side effects, another NSAID, celecoxib, has been shown to have less complications and can be prescribed. Amitriptyline and other tricyclic antidepressants are also effective in some individuals with hemicrania continua as a preventative treatment.

Individuals with hemicrania continua may obtain complete to near-complete relief of symptoms with proper medical attention and daily medication. Some people may not be able to tolerate long-term use of indomethacin and may have to rely on less effective NSAIDs.