What Causes Migraines?
The exact causes of migraines are unknown, although they are related to changes in the brain as well as to genetic causes. People with migraines may inherit the tendency to be affected by certain migraine triggers, such as fatigue, bright lights, weather changes, and others.
For many years, scientists believed that migraines were linked to expanding and constricting blood vessels on the brain's surface. However, it is now believed that migraines are caused by inherited abnormalities in certain areas of the brain.
There is a migraine "pain center" or generator in the brain. A migraine begins when hyperactive nerve cells send out impulses to the blood vessels, causing them to clamp down or constrict, followed by dilation (expanding) and the release of prostaglandins, serotonin, and other inflammatory substances that cause the pulsation to be painful.
What Triggers a Migraine?
Many migraines seem to be triggered by external factors. Possible triggers include:
- Emotional stress. This is one of the most common triggers of migraine headache. Migraine sufferers are generally highly affected by stressful events. During stressful events, certain chemicals in the brain are released to combat the situation (known as the "flight or fight" response). The release of these chemicals can provoke vascular changes that can cause a migraine. Repressed emotions surrounding stress, such as anxiety, worry, excitement, and fatigue can increase muscle tension and dilated blood vessels can intensify the severity of the migraine.
- Sensitivity to specific chemicals and preservatives in foods. Certain foods and beverages, such as aged cheese, alcoholic beverages, and food additives such as nitrates (in pepperoni, hot dogs, luncheon meats) and monosodium glutamate (MSG, commonly found in Chinese food) may be responsible for triggering up to 30% of migraines.
- Caffeine. Excessive caffeine consumption or withdrawal from caffeine can cause headaches when the caffeine level abruptly drops. The blood vessels seem to become sensitized to caffeine, and when caffeine is not ingested, a headache may occur. Caffeine itself is often helpful in treating acute migraine attacks.
- Changing weather conditions. Storm fronts, changes in barometric pressure, strong winds, or changes in altitude can all trigger a migraine.
- Menstrual periods
- Excessive fatigue
- Skipping meals
- Changes in normal sleep pattern
Migraines and Associated Conditions
There are some medical conditions that are more commonly associated with migraines, including:
- Chronic fatigue syndrome
- Raynaud's phenomenon (occurs when blood vessels narrow causing pain and discoloration usually in the fingers)
- Sleep Disorders
Are Migraines Hereditary?
Yes, migraines have a tendency to be hereditary. Four out of five migraine sufferers have a family history of migraines. If one parent has a history of migraines, the child has a 50% chance of developing migraines, and if both parents have a history of migraines, the risk jumps to 75%.
What Are the Symptoms of Migraines?
The symptoms of migraine headaches can occur in various combinations and include:
- A pounding or throbbing headache that often begins as a dull ache and develops into throbbing pain. The pain is usually aggravated by physical activity. The pain can shift from one side of the head to the other, or it can affect the front of the head or feel like it's affecting the whole head.
- Sensitivity to light, noise, and odors
- Nausea and vomiting, stomach upset, abdominal pain
- Loss of appetite
- Sensations of being very warm or cold
- Blurred vision
- Fever (rare)
Most migraines last about four hours although severe ones can last up to a week. The frequency of migraines varies widely among individuals. It is common for a migraine sufferer to get two to four headaches per month. Some people, however, may get headaches every few days, while others only get a migraine once or twice a year.
Types of Migraines
Symptoms that signal the onset of a migraine are used to describe two types of migraine.
- Migraine with aura (known as "classic" migraine)
- Migraine without aura (known as "common" migraine)
An "aura" is a physiological warning sign that a migraine is about to begin. Migraines with auras occur in about 20% to 30% of migraine sufferers. An aura can occur one hour before the attack of pain and last from 15 minutes to one hour. The symptoms always last less than one hour. Visual auras include:
- Bright flashing dots or lights
- Blind spots
- Distorted vision
- Temporary vision loss
- Wavy or jagged lines
There are also auras that can affect the other senses. These auras can be described simply as having a "funny feeling," or the person may not be able to describe the aura. Other auras may include ringing in the ears (tinnitis), or having changes in smell (such as strange odors), taste, or touch.
Rare migraine conditions include these types of neurological auras:
Hemiplegic migraine. Temporary paralysis (hemiplegia) or nerve or sensory changes on one side of the body (such as muscle weakness). The onset of the headache may be associated with temporary numbness, dizziness, or vision changes. These need to be differentiated from a stroke.
Retinal migraine. Temporary, partial, or complete loss of vision in one eye, along with a dull ache behind the eye that may spread to the rest of the head.
Basilar artery migraine. Dizziness, confusion, or loss of balance can precede the headache. The headache pain may affect the back of the head. These symptoms usually occur suddenly and can be associated with the inability to speak properly, ringing in the ears, and vomiting. This type of migraine is strongly related to hormonal changes and primarily affects young adult women.
Status migrainosus. A rare and severe type of migraine that can last 72 hours or longer. The pain and nausea are so intense that people who have this type of headache often need to be hospitalized. Certain medications, or medication withdrawal, can cause this type migraine syndrome.
Ophthalmoplegic migraine. Pain around the eye, including paralysis in the muscles surrounding the eye. This is an emergency medical condition, as the symptoms can also be caused by pressure on the nerves behind the eye or an aneurysm. Other symptoms of ophthalmoplegic migraines include droopy eyelid, double vision, or other vision changes. Fortunately, this is a rare form of migraine.
Migraines without auras are more common, occurring in 80% to 85% of migraine sufferers. Several hours before the onset of the headache, the person can experience vague symptoms, including:
- Fatigue or tiredness
How Are Migraines Treated?
There is no cure for migraines. However, there are many drugs available to treat or even prevent some migraines. Some people may also reduce the frequency of migraines by identifying and avoiding triggers that lead to the migraine such as drinking red wine or getting too little sleep (see the triggers above).
- Pain relief. Over-the-counter drugs are often effective pain relievers for some people with migraines. The main ingredients in pain-relieving medications are ibuprofen (for example, Motrin), aspirin, acetaminophen (Tylenol), and caffeine. Be cautious when taking over-the-counter pain-relieving medications because sometimes they can contribute to a headache, or their overuse can cause rebound headaches or a dependency problem. If you are taking any over-the-counter pain medications more than three times a week or daily, it's time to see your doctor. He or she can suggest prescription medications that may be more effective.
- Antinausea drugs. Your doctor can prescribe medication to relieve the nausea that often accompanies migraines.
- Abortive medicines (stop migraines). There are some special medications that if used at the first sign of a migraine, may stop the process that causes the headache pain. These medications can also stop the headache pain itself. By stopping the headache process, these drugs help prevent the symptoms of migraines, including pain, nausea, light-sensitivity, etc. The medicine works by constricting the blood vessels, bringing them back to normal, and relieving the throbbing pain.
- Biofeedback. Biofeedback helps people learn to recognize stressful situations that trigger migraines. If the migraine begins slowly, many people can use biofeedback to stop the attack before it becomes full blown.
- Magnetic stimulation. The Cerena Transcranial Magnetic Stimulator (TMS) is a prescription device placed on the back of the head at the onset of a migraine with aura. It then releases a pulse of magnetic energy and stimulates part of the brain, which may stop or lessen pain.
All of these treatments should be used under the direction of a headache specialist or doctor familiar with migraine treatments. As with any medication, it is important to carefully follow the label instructions and your doctor's advice.
Can Migraines Be Prevented?
Yes, migraines can be prevented. You can reduce the frequency of your migraine attacks by identifying and then avoiding migraine triggers. You can keep track of your headache patterns and identify headache triggers by using a headache diary.
Recalling what was eaten prior to an attack may help you identify those foods that cause your migraines and make the necessary dietary changes to avoid these triggers in the future.
Stress management and coping techniques, along with relaxation training, can help prevent or reduce the severity of the migraine attacks.
Women who often get migraines around their menstrual period can take preventive therapy when they know their period is coming.
Migraine sufferers also seem to have fewer attacks when they eat on a regular schedule and get adequate rest. Regular exercise -- in moderation -- can also help prevent migraines.
When lifestyle changes aren't effective at preventing migraines, there are other options.
When the headaches are severe, occur more than two or three times a month, and are significantly interfering with normal activities, your doctor may prescribe preventive medication. Preventive medications reduce the frequency and severity of the headaches and are generally taken on a regular, daily basis.
Also, Cefaly is the first FDA-approved device for preventing migraines in people over age 18. The portable headband-like device gives electrical impulses on the skin at the forehead. This stimulates the trigeminal nerve, which is associated with migraine headaches. Cefaly is used once a day for 20 minutes, and when it's on you'll feel a tingling or massaging sensation.