What Is Hemicrania Continua?

Introduction

Hemicrania continua is a rare and severe form of daily headaches. It is a continuous headache disorder, which is known to affect more women than men. It is a primary headache disorder, which means that an underlying cause has already been ruled out by carefully examining the medical history and other specific tests.

The main symptom of hemicrania continua is a continuous unilateral pain in the head. The pain can range from mild, moderate to severe. These constant headache episodes can get worse and tend to persist for up to 20 minutes to several days. During this period, the person suffering from these bouts of headaches may experience a combination of autonomic features such as watering of the eyes, the eyes turning red and blurry, blockage of the nasal passage, drooping of the eyelid, and a runny nose. These symptoms usually occur on the same side of the pain.

Since hemicrania continua is a severe form of headache, it is often confused with migraine headaches and cluster headaches. The pain due to hemicrania continua mostly occurs just on one side of the head or face. The term literally means “pain in half the head” in Latin.

Individuals suffering from this type of headache suffer from daily and constant pain. In this condition, individuals experience pain all the time. Usually, the pain would stay at a consistent level without any changes. Sometimes, the pain tends to quickly increase in severity or spike up for certain period of time.

Most of the time, it can be quite difficult to distinguish between various types of headaches. Individuals may experience different types of headaches at various times of their life due to varying reasons. A person suffering from hemicrania continua can also experience other types of headaches such as migraine attacks. 

Symptoms

Below are the symptoms of hemicrania continua:

• Daily and constant pain on one side of the face or head
• Excessive sweating
• Long-term pain
• Drooping eyelid (seen on the same painful side of the head or face)
• Eyes turning red (on the same painful side of the head)
• Runny nose

Causes

The exact cause of hemicrania continua is still unknown. However, alcohol intake or any kind of physical exertion tend to worsen the pain. This syndrome has been newly discovered, so there are still research studies being carried out to learn more about it in detail.

Diagnosis

There are no specific tests available to accurately diagnose the condition. Most doctors would primarily base their diagnosis on the patient's symptoms. The pain caused by hemicrania continua should be a constant one. Although, at times, periodic spikes of pain can be experienced. The pain would mostly occur on one side of the head or face.

The symptoms should also be experienced by the individual for at least a period of three months or more. Since the condition is known to mimic other types of headaches, the doctor may recommend an MRI scan or a CT scan to rule out the possibility of other underlying medical conditions.

Moreover, as part of the diagnosis, the doctor would want to ensure that the pain would also respond to a certain medication called indomethacin, which is usually prescribed when it comes to treating headaches due to hemicrania continua. If the pain responds well to indomethacin, then the patient most likely suffers from hemicrania continua. However, it is still important to go through the recommended imaging scans to have an accurate diagnosis.

It is also beneficial to maintain a diary, so the doctor can effectively evaluate your symptoms and response to the treatment. The following are useful information that you can take note in your diary:

• The exact location of pain.
• When does the pain tend to worsen?
• How often does the pain worsen in a given day?
• How long do these periods of worsening headaches last?
• Do you experience other symptoms that accompany your headaches?

Hemicrania continua can also mimic other neurological disorders. The carotid arteries or other blood vessels that are servicing the brain can develop plaques, clots, or splitting, which would occur along the walls and cause pain that is quite similar to hemicrania continua. Tumors in the pituitary gland or other central areas of the brain can also lead to symptoms that are similar to hemicrania continua. For these reasons, patients may undergo imaging tests such as a CT scan or an MRI scan before the doctor can confirm the diagnosis. 

When to seek medical help?

See a doctor if your headache persists for more than three days or when you experience recurring headaches once or twice a week. You also need to consult a doctor if you experience the following:

• You always need to take over-the-counter medications to get pain relief from your headache. 
• Over-the-counter pain medications seem to be not working anymore.
• Your headaches prevent you from performing daily normal functions.
• Your headaches tend to worsen over time.

Below are also other instances when your symptoms would need immediate medical attention:

• A severe headache that occurs all at once.
• A headache that is followed by a seizure attack or convulsion.
• Other symptoms such as neck pain, feeling confused, and fever in some cases.
• A headache along with other symptoms such as vision problems, speech difficulties, and numbness.
• Recurring headaches after a head injury.
• A persistent headache even after taking pain medications.

Treatment

The main treatment of hemicrania continua is a type of nonsteroidal anti-inflammatory drug (NSAID) called indomethacin. It is a prescription medicine that works similarly to naproxen or ibuprofen. However, indomethacin is proven to be quite effective in providing relief from pain due to hemicrania continua.

The doctor would mostly start off with a low indomethacin dose, which is at 25 mg to be taken along with meals three times a day. Based on the response of the treatment, the doctor can adjust the dose until it provides relief from the headache pain. The dose of this medicine can sometimes be increased up to 75 mg to be taken three times a day or more to achieve pain relief. However, this medicine also has certain gastrointestinal side effects. There would be a need to take another medicine to reduce the production of stomach acid and to prevent ulcers from forming. Proton pump inhibitors such as lansoprazole and omeprazole can help provide protection to a certain extent.

Indomethacin is known to cause stomach ulcers, esophageal ulcers, intestinal ulcers, and bleeding in certain cases. Indomethacin is processed through the kidneys, so certain kidney problems may arise if this medication is taken in high doses.

After taking this medicine, few individuals would experience symptoms such as nausea, vomiting, depression, or tiredness. Other individuals, mostly those who have a history of migraines tend to initially develop a severe form of headache after taking indomethacin. Most individuals can tolerate indomethacin in lower doses while others find it difficult.

If an individual is unable to tolerate the side effects of indomethacin, then the doctor can prescribe other drug alternatives, which may include:

• A lower dose of indomethacin (if tolerated)
• Tricyclic antidepressants as part of the preventive treatment option
• Celecoxib (another type of NSAID)
• Nerve blockers are used when other forms of treatment do not positively respond
• Antidepressants such as amitriptyline is used as a preventive treatment
• Melatonin is a natural hormone with a chemical structure quite similar to indomethacin.

There have been a few cases wherein hemicrania continua responded to melatonin treatment alone. However, those individuals also found relief with low doses of indomethacin.

Conclusion

Treatment using indomethacin is quite effective when it is coupled with medical care and regular visits to the doctor. Most of the time, individuals who suffer from hemicrania continua are able to live their life with little or without pain while treatment is going on.

If an individual is unable to use indomethacin for a longer duration, then the doctor can prescribe another type of NSAID. Although other NSAIDs can help, they are not that quite effective when it comes to providing pain relief due to hemicrania continua.