migraines and other primary headaches arise from disturbances within the central nervous system. These disturbances trigger a cascade of chemical changes that cause inflamed blood vessels and neurological symptoms, including pain.

If you suffer from migraine headaches, you're not alone. About 12 percent of the U.S. population experience migraines

Of all the possible headache types, migraines are among the most severe and disabling. In fact, migraines are so widespread that they are ranked by the World Health Organization (WHO) as number 19 among all diseases that cause disability worldwide. A person who suffers with migraine typically has moderate to severe headaches along with other symptoms that include nausea, vomiting or sensitivity to light and sound. Headaches occur more commonly on one side of your head and can last from four to 72 hours, if untreated.

Migraines involve recurrent attacks of moderate to severe pain that is throbbing or pulsing and often strikes one side of the head. Untreated attacks last from 4 to 72 hours. Other common symptoms are increased sensitivity to light, noise, and odors; and nausea and vomiting. Routine physical activity, movement, or even coughing or sneezing can worsen the headache pain.

Who Gets Migraines?

• People in the same family get migraines. Certain types of migraine are inherited or passed from one generation to the next within a family.

• Migraines affect women three times more often than men. The female hormone estrogen is believed to play a role in why more women than men suffer with this painful condition. 

• Migraines often begin in childhood or the teenage years.

Types of Migraine. The two major types of migraine are:

• Migraine with aura, previously called classic migraine, includes visual disturbances and other neurological symptoms that appear about 10 to 60 minutes before the actual headache and usually last no more than an hour. Individuals may temporarily lose part or all of their vision. The aura may occur without headache pain, which can strike at any time. Other classic symptoms include trouble speaking; an abnormal sensation, numbness, or muscle weakness on one side of the body; a tingling sensation in the hands or face, and confusion. Nausea, loss of appetite, and increased sensitivity to light, sound, or noise may precede the headache.
• Migraine without aura, or common migraine, is the more frequent form of migraine. Symptoms include headache pain that occurs without warning and is usually felt on one side of the head, along with nausea, confusion, blurred vision, mood changes, fatigue, and increased sensitivity to light, sound, or noise.

Other types of migraine include:

• Abdominal migraine mostly affects young children and involves moderate to severe pain in the middle of the abdomen lasting 1 to 72 hours, with little or no headache. Additional symptoms include nausea, vomiting, and loss of appetite. Many children who develop abdominal migraine will have migraine headaches later in life.
• Basilar-type migraine mainly affects children and adolescents. It occurs most often in teenage girls and may be associated with their menstrual cycle. Symptoms include partial or total loss of vision or double vision, dizziness and loss of balance, poor muscle coordination, slurred speech, a ringing in the ears, and fainting. The throbbing pain may come on suddenly and is felt on both sides at the back of the head.
• Hemiplegic migraine is a rare but severe form of migraine that causes temporary paralysis-sometimes lasting several days-on one side of the body prior to or during a headache. Symptoms such as vertigo, a pricking or stabbing sensation, and problems seeing, speaking, or swallowing may begin prior to the headache pain and usually stop shortly thereafter. When it runs in families the disorder is called Familial Hemiplegic Migraine (FHM). Though rare, at least three distinct genetic forms of FHM have been identified. These genetic mutations make the brain more sensitive or excitable, most likely by increasing brain levels of a chemical called glutamate.
• Menstrually-related migraine affects women around the time of their period, although most women with menstrually-related migraine also have migraines at other times of the month. Symptoms may include migraine without aura (which is much more common during menses than migraine with aura), pulsing pain on one side of the head, nausea, vomiting, and increased sensitivity to sound and light.
• Migraine without headache is characterized by visual problems or other aura symptoms, nausea, vomiting, and constipation, but without head pain. Headache specialists have suggested that fever, dizziness, and/or unexplained pain in a particular part of the body could also be possible types of headache-free migraine.
• Ophthalmoplegic migraine an uncommon form of migraine with head pain, along with a droopy eyelid, large pupil, and double vision that may last for weeks, long after the pain is gone.
• Retinal migraine is a condition characterized by attacks of visual loss or disturbances in one eye. These attacks, like the more common visual auras, are usually associated with migraine headaches.
• Status migrainosus is a rare and severe type of acute migraine in which disabling pain and nausea can last 72 hours or longer. The pain and nausea may be so intense that sufferers need to be hospitalized.

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Migraine Reasons

Migraines begin when the blood vessels in and around your brain dilate. In the past, medical experts thought that a shift of blood flow caused the blood vessels inside the head to dilate. Now, many medical experts believe that a disorder in the central nervous system (CNS) is the root of the problem.

Each blood vessel is supplied by tiny nerves, which cause it to dilate or constrict as needed. Experts believe that some sort of disorder in the CNS may trigger a stream of abnormal messages that tell the tiny nerves to dilate the blood vessels at the wrong time. This, in turn, may cause migraine pain and symptoms.