What are the other Names for this Condition? (Also known as/Synonyms)

• Continuous Headache
• Continuous One-Sided Headache
• HC (Hemicrania Continua)

What is Hemicrania Continua? (Definition/Background Information)

• Hemicrania Continua (HC) is uncommon type of severe headache that is not caused by an underlying condition; meaning, it is a form of primary headache. In this condition, there is pain in one side (or one half) of the head (hence termed Hemicrania Continua). HC is more common in adult women
• There are no well identified risk factors for Hemicrania Continua. The pain is often continuous and occurring daily, lasting from a minimum period of about 20 minutes to a several hours to even days; it can be sometimes mild or moderate in intensity. However, the pain remains on the same side of the head
• The signs and symptoms of Hemicrania Continua may be managed through suitable medications and nerve stimulation. Severe cases may affect one’s work and life. The prognosis can vary from one individual to another, but is mostly good with adequate therapy

Who gets Hemicrania Continua? (Age and Sex Distribution)

• Hemicrania Continua is a rare migraine-like condition. The presentation of symptoms reportedly occurs between 5-67 years of age, although most cases are noted into adulthood
• Both males and females may be affected, however, the condition is more common in women
• Worldwide, individuals of all racial and ethnic groups may be affected

What are the Risk Factors for Hemicrania Continua? (Predisposing Factors)

• Currently, no risk factors have been clearly identified for Hemicrania Continua

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Hemicrania Continua? (Etiology)

• Presently, the cause of Hemicrania Continua is not well-understood
• Overuse of medications, such as analgesics, has been suggested as a possible cause for this condition

What are the Signs and Symptoms of Hemicrania Continua?

Hemicrania Continua may last for a period of less than an hour (about 20 minutes) to even several days. The signs and symptoms may include:

• Constant mild-to-moderate pain on one side of the head (unilateral) without pain-free periods
• Periods of more intense or severe migraine-like pain (exacerbations) may be observed
• In most of the cases, only one side of the head is involved. Occasionally though, pain on both sides of the head may be noticed

How is Hemicrania Continua Diagnosed?

Hemicrania Continua is diagnosed on the basis of the following information:

• Complete physical examination and assessment of signs and symptoms
• Thorough analysis of personal and family medical history
• Neurological examination by a qualified healthcare provider, if necessary
• Laboratory tests may be performed to rule out other causes of pain
• Computerized tomography (CT) scan of the head
• Magnetic resonance imaging (MRI) scan of the brain
• Differential diagnosis to rule out other conditions that may present with similar signs and symptoms may be undertaken

Criteria that must be met for the condition to be considered Hemicrania Continua:

• Daily or continuous headache for at least 3 months with episodes of intense pain
• The headache does not shift sides
• There are no pain-free periods
• During severe pain, watering or red eyes, runny nose or nasal congestion, and droopy eyelid on the same side of the body as the headache, may be noted
• The headache is completely responsive to indomethacin (a prescription NSAID)

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Hemicrania Continua?

The complications of Hemicrania Continua may include:

• Non-tolerance of long-term indomethacin use
• Gastrointestinal discomfort
• Temporomandibular joint (TMJ) pain
• Recurrence of the headaches following treatment
• Work and daily life may be severely affected
• Reduced quality of life

Complications may occur with or without treatment, and in some cases, due to treatment also.

How is Hemicrania Continua Treated?

Hemicrania Continua is treated in the following manner:

• Daily administration of indomethacin based on the healthcare provider’s evaluation
• Acid-suppressing medication for those who develop gastrointestinal discomfort
• Other non-steroidal anti-inflammatory medications (NSAIDs), such as celecoxib, for those who develop severe side effects to indomethacin
• Occipital nerve stimulation
• Hypothalamic and brain stem activation

Regular medical screening at periodic intervals with tests and physical examinations are recommended.

How can Hemicrania Continua be Prevented?

The exact cause of Hemicrania Continua is not known, and therefore, no methods or guidelines are currently available for its prevention.

• If an individual is using medications in excess, consulting a healthcare professional for safe withdrawal of the medication may help reduce the severity of signs and symptoms
• Tricyclic antidepressants have been prescribed for preventive treatment in some affected individuals
• Active research is currently being performed to explore the possibilities for treatment and prevention of conditions such as Hemicrania Continua

What is the Prognosis of Hemicrania Continua? (Outcomes/Resolutions)

• In most cases, the prognosis of Hemicrania Continua is good with a complete or near-complete resolution being observed through regular medication use
• Some individuals are known to only have a single episode of the condition their entire lifetime, while for other, Hemicrania Continua may recur later in their life
• Some individuals may experience unpleasant side effects to indomethacin and may be prescribed alternative (and less effective) medications (such as other NSAIDs). These medications may not be as effective as indomethacin though

Additional and Relevant Useful Information for Hemicrania Continua:

The following DoveMed website link is a useful resource for additional information:

http://www.dovemed.com/diseases-conditions/rare-disorders/