Cluster headaches, aka "suicide headaches," can literally last for weeks or months.
Generally followed by a remission period, which in turn can also last for several months (or even years), the headache's cyclical patterns, or "clusters," are exactly how the condition's name was derived.
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They are so painful that “one female patient likened it to giving birth to 100 babies without an epidural," Dr. Brian Grosberg, director of the Inpatient Headache Program at Montefiore Headache Center in Bronx, N.Y., told FOXNews.com. "It’s really bad.”
However, they are the least common form of headaches, and 90 percent of sufferers are male.
So, how do you know if you have a true cluster headache requiring medical attention, as opposed to a migraine or tension headache?
"Cluster headaches are always one one side of the head, and they never switch sides," Grosberg said.
Cluster headaches are divided into two forms: episodic and chronic pattern.
Chronic headaches, which are more common, can occur every day, up to eight times a day.
Episodic headaches are random and are usually triggered by a stressful event.
Grosberg said symptoms can include:
— Excruciating pain in or around one eye;
— One-sided pain;
— Excessive tearing;
— Redness in the affected eye;
— Stuffy or runny nose on the affected side;
— Drooping eyelid;
— Decreasing pupil.
While migraine sufferers tend to retire to a dark room when faced with their pain, cluster sufferers are often agitated and restless, Grosberg said.
Triggers include stress, smoking and drinking alcohol.
If you suspect you are suffering from cluster headaches, consult with your health care provider.
Grosberg said the following are ways to treat them:
— Calcium channel blockers, as a preventive.
— Sumatriptans, which are available as an injectable, nasal spray and tablet form, as an acute treatment.
— Oxygen therapy can be given via a non-rebreather mask at 100 percent oxygen at 10 to 12 per liters for 15 to 20 minutes.
— Steroids, which can be used as transitional treatment.