Typically the symptoms include a constant ache, which affects both sides of the head with tightening of the neck muscles and a feeling of pressure behind the eyes.
Cluster headaches begin quickly and are one-sided, short-lived, excruciatingly painful headaches.
They can recur frequently for several weeks and then subside, but another bout may develop some months, or up to a year, later. Sleep is often disrupted, with the headache causing you to wake up at the same time each night. The eye on the side of the headache often becomes inflamed and watery, and you might have a blocked nose on the affected side.
Approximately 80% of people who have cluster headaches are men. It is a fairly rare condition, affecting around one in 1,000 people.
Migraines are different from tension-type and cluster headaches and usually cause symptoms of sickness or nausea in addition to a severe, one-sided, throbbing headache. However, some people experience both migraines and tension-type headaches.
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