Cluster headache is characterized by excruciating pain that affects only one side of the head, often focusing on the area around the eye.
It is the most severe form of headache and, fortunately, also the rarest. It affects one in 500-1000 people. It can occur at any age, but tends to appear after the age of 20 and mainly affects males. The people most at risk appear to be smokers.
The causes of cluster headache are not yet clear, but it is believed that they must be sought in the activity of an area of the brain, called hypothalamus, in which the so-called internal biological clock which controls sleep-wake rhythms. Genetic predisposition is thought to play an important role in its emergence as it sometimes affects multiple members of the same family.
Typically, the headache presents with repeated attacks, gathered in "clusters", lasting several weeks (usually 4 to 12 weeks). They are named active periods and alternate with headache-free phases, the so-called periods of remission, which can last for months or, sometimes, years.
Headache fits can recur every year, for several years, and can last for a lifetime, but generally tend to subside over time.
However, there are several treatments available that can control them.
Cluster headache attacks begin suddenly and without warning. The pain is severe in intensity and is often described as a sharp, stabbing, burning sensation that affects one side of the head. The pain is felt around the eye and temple, sometimes extending to the face, always appearing on the same side at each single episode.
People with cluster headaches during an attack typically appear restless and agitated from severe pain, cannot sit still, and may react by walking back and forth.
Headache is usually accompanied by one or more of the following disorders (symptoms), always felt on the same side where the pain appears:
- redness and tearing of the eye
- swollen eyelid or lowered
- narrowing of the pupil
- facial sweating
- closed or runny nostril
- ear redness
The attacks last from 15 minutes to three hours and can recur one to eight times a day.
Model of the attacks
Cluster headache is characterized by a cyclical pattern. Crises tend to recur at certain times of the year, generally in spring and autumn, and usually at the same time of day. It is quite common for them to begin at night, about two hours after falling asleep.
Some people associate headache attacks with the following triggers:
- drinking alcoholic beverages
- high temperatures
- physical activity
- strong smells, such as those given off by perfumes, paint or petroleum
THE active periods, those in which the headache occurs, have a variable duration from several weeks to a few months. They follow periods of remission, in which the headache is absent, which can last from a few months to several years, before the attacks recur.
When headache crises are separated by a remission period of one or more months it is referred to as episodic cluster headache. If the remission period is less than one month, or the attacks last for at least 12 months without remission, it is chronic cluster headache.
About 10-20% of cluster headache cases are chronic.
When to see your doctor
As soon as a headache with the typical characteristics of cluster headache occurs, it is necessary to contact the family doctor who may request the execution of some investigations. Normally the assessment (diagnosis) of cluster headache is carried out on the basis of the disorders ( symptoms) reported but, at times, a CT scan or MRI of the brain may be necessary to rule out the presence of other diseases that cause similar disorders.
If a cluster headache is ascertained (diagnosed), the treating physician usually asks for a visit to the neurologist, a physician who specializes in nervous system disorders, to discuss the various options for treatment.
Cluster headache does not represent a health hazard, but it can seriously compromise the quality of life, so it is important to consult a specialist who can suggest an effective therapy for this condition.
Seizures cannot be treated with over-the-counter pain relievers, such as acetaminophen, because they take too long to work.
There are, however, three types of treatment that can alleviate pain if used at the first signs of the attack:
- sumatriptan injections subcutaneously, they can be practiced alone up to twice a day
- nasal sprays based on sumatriptan or zolmitriptan, they can be used by those who cannot stand injections
- pure oxygen therapy, inhaled through a face mask
These therapies usually begin to act on cluster headaches, reducing pain within 15-30 minutes of their use.
Your doctor may prescribe a treatment that helps prevent cluster headache attacks (prophylaxis). Prophylaxis should be started as soon as the attack occurs and continued until it ends.
The recommended preventive cure is verapamil, administered in the form of tablets to be taken several times a day. An electrocardiogram (ECG) is required while using this drug as it may cause heart problems.
If verapamil is not effective, several alternative therapies are available, such as drugs based on corticosteroids, lithium carbonate and occipital nerve blocks (injections of local anesthetic in the nape of the neck).
A promising treatment has recently been introduced, the external stimulation of the vagus nerve, based on the use of a device capable of stimulating the vagus nerve, which crosses the neck.
The effectiveness of the different types of treatment, however, varies from one person to another. You may need to try several therapies before finding the one that works best for you.In-depth link
International Headache Society (IHS). The International Classification of Headache Disorders 3rd edition
Niguarda Hospital. Headache