COMMON FORMS OF HEADACHES: MIGRAINE

Migraine is not just a name for an unusually bad headache; it is a specific diagnosis, involving pain that begins on one side of the head, often accompanied by nausea and sensitivity to light and sounds. Many migraine sufferers experience the sensation of an "aura" in their visual field, typically some form of disturbance such as flashing lights or blind spots, along with numbness or weakness on one side of the body or slurred speech, all signals of an ensuing bad headache. Most people report pain behind or around one eye and always on the same side of the head - a pain that can last for hours or days and then disappear. A migraine can strike at any time, although the hormonal changes around menstruation and ovulation often seem to set off migraines in women, who are three times more likely to get migraines as are men. Migraines can occur in children as young as 2 years, with incidences peaking from the mid-20s through middle age and then trailing off around age 55.

Although migraines are believed to run in families, and the hormonal influences seem to be well established, findings about other forms of migraine "triggers" seem to be highly speculative at best. Patients report that migraines can be triggered by emotional stress, the weather, certain foods, lack of sleep, and a litany of other causes. When tested under laboratory settings, however, much of this evidence is inconclusive. What is known is that migraines occur when blood vessels dilate in the membrane that surrounds the brain. Historically, treatments have centered on reversing or preventing this dilation, with the most common treatment derived from the rye fungus ergot. Today, many fast-acting ergot compounds are available by nasal spray, vastly increasing the speed of relief to patients. However, ergot drugs have many side effects, the least of which may be that they are habit forming, causing users to wake up with "rebound" headaches each morning after use.

Critics of the blood vessel dilation theory question why only blood vessels of the head are dilated in these situations. They also wonder why, if the dilation causes vessels to press against nerves and inflict pain, aren't joggers and people who take a lot of hot baths more prone to migraine attacks? Opponents of blood vessel dilation theory suggest that the key to understanding the origin of migraines lies in the cortex of the brain, where certain pain sensors are stimulated.

According to pioneering work by Harvard University neurology professor Michael Moskowitz, triggers, such as caffeine or wine, set off an electrical ripple on the surface of the cortex. Waves of nerve cells fire and then go quiet, creating an aura. This spurs a reaction in the meninges, the membranes above the cortex. The meninges contain endings of the brain's major nerve, the trigeminus, which release chemicals that inflame nearby tissues. The result is pain.

Other doctors believe that pain signals start deep in the brain in areas normally rich in the pain-killing chemical serotonin. Migraines are started by disturbances that keep the pain-regulating chemicals from doing their job. Susceptibility to these disturbances may be hereditary. This theory would explain why drugs that interact with serotonin work to reduce headaches. (It must be said that there is no proof that serotonin irregularities cause headaches, only that serotonin drugs work.)

When true migraines occur, relaxation is only minimally effective as a treatment. Often, strong pain-relieving drugs prescribed by a physician are necessary. In 1994, the FDA approved Imitrex, a drug tailor-made for migraines that works for about 80 percent of those who try it. But the cost of a single dose is a stunning 14 dollars per pill, and second doses are often needed. In addition, its side effects make Imitrex inappropriate for anyone having uncontrolled high blood pressure or heart disease. Recently, treatment with lidocaine has also shown promising results, and newer drugs called triptans, such as Zomig, Amerge, and Maxalt, are now available. All triptans, however, are cleared from the body in a few hours and the migraine sometimes returns.