Humans have suffered headaches since before the beginning of recorded history. Archaeological evidence suggests that our prehistoric ancestors may have tried to ease headache pain by drilling holes into their skulls. Recent research has advanced our understanding of what causes headaches and has helped doctors find more effective--and less invasive--relief for the 45 million Americans who currently suffer from chronic headaches.*
What's Behind that Ache?

  Specialists have long divided headaches into three groups: tension, migraine and cluster. The cause of cluster headaches remains unclear, but recent breakthroughs have led many scientists to revise their theories about what causes tension and migraine headaches. 

  Researchers once blamed muscle tension for tension headaches, and irregular blood flow to the brain for migraines. Today, more and more scientists believe that both migraines and tension headaches stem from chemical or neurological abnormalities in the brain. The following descriptions may help distinguish between the different kinds of headaches.

• Tension-type headaches. According to the National Headache Foundation, 90% of all headaches are tension. The pain usually affects the entire head or the back of the neck, and may feel like a band tightening around the head. Possible causes include depression or other emotional problems, a sleep disorder, high blood pressure, excess caffeine or the wrong eyeglass prescription.
• Migraine. These headaches usually involve intense pain. They can last from several minutes to several days and drastically alter a sufferer's quality of life. Migraine sufferers may experience additional symptoms such as nausea and vomiting, as well as warning signs. Sparkling flashes of light, dizziness, weakness and a variety of other visual disturbances may signal an impending headache. Emotional stress, alcohol, certain foods, hormone replacement therapy, birth control pills and a family history of migraines may contribute to the condition. 
• Cluster headaches affect an estimated 1 million Americans, according to the NHF. This kind of headache causes incredibly severe pain, often an intense burning or boring feeling in or around one eye, which may last from 30 minutes to several hours. Additional symptoms may include bloodshot and teary eyes, runny nose and sweating. Attacks usually occur at the same time each day, often one or two hours after bedtime. The headaches may recur for days, weeks, months or even years, then lapse into remission. Cluster headaches primarily affect men ages 20 to 40, and may be linked to drinking alcohol, smoking, eating certain foods and changing weather patterns. 

  The chemical or neurological abnormalities that cause headaches are often provoked by certain environmental, lifestyle or dietary factors. By tracking the time and circumstances surrounding your headaches in a diary, you and your doctor may be able to pinpoint what triggers your headaches. Identifying your triggers, then devising a plan to manage or avoid them, may help you prevent some or all headaches. Common triggers include alcohol, some foods and food additives, stress, irregular sleep patterns, polluted air or fluorescent, glaring or flickering lights. 

  If efforts to control triggers fail, the following techniques may help relieve the discomfort:

• Relaxing in a quiet, dark room.
• Applying either hot or cold packs to the head or neck. 
• Massaging the neck or base of the skull. 
• Taking over-the-counter analgesics.

  Prescription medications, oxygen therapy or alternative techniques, such as biofeedback or stress reduction, may provide additional relief. Talk to your doctor to find out if one of these methods may be right for you.