This article about headache is appealing for those interested about this topic.

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A cluster headache is one of the most excruciating kinds of headache, surpassing even the pain of an average migraine in intensity. It is generally described as a sharp, stabbing type of pain that lacks the throbbing, pulsating quality of a migraine. Cluster headache attacks happen extremely fast - one minute the person feels perfectly normal, the next minute like they are being stabbed through the eye. Generally, the pain is located on just one side of the head.

Cluster headaches often occur in tandem with other symptoms, which are usually limited to the side of the face that the pain is on. For example, the victim’s pupils may shrink in size, one eye may suddenly start overflowing with tears or the eyelid may start drooping, and the affected side of the face may swell or turn red.

The defining feature of a cluster headache is that the attacks are experienced in waves or cycles, also called clusters. Clusters can last from 2 days to a couple of weeks. During the cluster period, attacks usually occur at least once per day, although they can occur more often. Many times, cluster attack victims are jerked out of a sound sleep by a severe headache. The length of each individual headache is relatively short, however; anywhere from a half hour to an hour and a half.

After the cluster period ends, the victim may experience a pain-free period of remission, when the headaches do not occur. People who experience cluster periods followed by remission have what is known as episodic cluster headache. Other people have chronic cluster headache, with no remission period between cycles.

Causes of Cluster Headache 

Cluster headaches are even more shrouded in mystery than tension headaches and migraines. Nobody is quite sure what causes these painful attacks, and the scientific hypotheses we have so far are not very detailed. For example, some researchers believe that cluster headaches are caused by a disruption in the nerve system that carries sensations from your head to your brain. This system of nerves is called the trigeminal system.

Other doctors believe that the pain starts with blood vessels buried deep in your head, such as the arteries that run through your sinuses. The hypothalamus, the control center for the body’s circadian rhythms or “biological clock,” is probably involved as well. That would explain why cluster attacks occur in such a regular pattern.