Although many people use the term "migraine" to describe any severe headache, a migraine headache is the result of specific physiologic changes that occur within the brain and lead to the characteristic pain and associated symptoms of a migraine.
Migraine headache are usually associated with sensitivity to light, sound, and smells. In addition, many patients experience nausea or vomiting. The headache of a migraine often involves only one side of the head but in some cases, patients may experience pain bilaterally or on both sides. The pain of a migraine is often described as throbbing or pounding and it may be made worse with physical exertion.
In some cases, patients with migraines experience specific warning symptoms, or an aura, prior to the onset of their headache. These warning symptoms can range from flashing lights or a blind spot in one eye to numbness or weakness involving one side of the body. The aura may last for several minutes, and then resolves as the head pain begins or may last until the headache resolves. For patients who have never experienced an aura, the symptoms can be frightening and can mimic the symptoms of a stroke.
Not all headaches represent migraines, and migraine is not the only condition that can cause severe and debilitating headaches. For example, cluster headaches are very severe headaches that affect one side of the head in a recurrent manner (occurring in a "cluster" over time). The pain is sometimes described as "drilling," and can be worse than migraine pain in some cases. Cluster headaches are less common than migraine.
Tension headaches are a more common cause of headache. Thee occur due to contraction of the muscles of the scalp, face, and neck.
What are migraine triggers?
Many factors have been identified as migraine triggers.
The normal hormone fluctuations which occur with regular menstrual cycles may predispose some women to experience migraine headaches.
Some types of oral contraceptives (birth control pills) can trigger migraines. Various foods such as:
· Red wines
· Aged cheeses
· Preservatives used in smoked meats ( nitrates)
· Monosodium glutamate
· Artificial sweeteners
· Chocolate
· Dairy products
· Oversleeping
· Alcohol beverages
· Stress
· Exposure to strong stimuli, such as bright lights, loud noises, or strong smells.
· Changes in barometric pressure have been described as leading to migraine headaches.
Not every individual who has migraines will experience a headache when exposed to these triggers. If a person is unsure what his or her specific triggers might be, maintaining a headache diary can be beneficial to identify those individual factors which lead to migraine.
What causes migraines?
The specific cause of migraines is not known, but there may be fluctuations in certain neurotransmitters, chemicals that send messages between brain cells. These changes may predispose some people to develop migraine headaches.
Up to 25% of people experience a migraine headache at some point in their life. Most migraine sufferers are female. It is estimated that after adolescence, the ratio of female to male patients who experience migraines is about 3:1. There seems to be a genetic predisposition to migraine, as there is often a strong family history of migraine in patients with this disorder.
What are the signs and symptoms of migraines?
The most common symptoms of migraine are:
· Severe, often "pounding," pain, usually on one side of the head
· Nausea and/or vomiting
· Sensitivity to light
· Sensitivity to sound
· Eye pain
The International Headache Society defines episodic migraine as being unilateral, pulsing discomfort of moderate-to-severe intensity, which is aggravated by physical activity and associated with nausea and/or vomiting as well as photophobia and/or phonophobia (sensitivity to light and sound). A migraine headache typically lasts for several hours up to several days.
Many patients describe their headache as a one-sided, pounding type of pain, with symptoms of nausea and sensitivity to light, sound, or smells (known as photophobia, phonophobia, and osmophobia). In some cases, the discomfort may be bilateral. The pain of a migraine is often graded as moderate to severe in intensity. Physical activity or exertion (walking up stairs, rushing to catch a bus or train) will worsen the symptoms.
Up to one-third of patients with migraines experience an aura, or a specific neurologic symptom, before their headache begins. Frequently, the aura is a visual disturbance described as a temporary blind spot which obscures part of the visual field. Flashing lights in one or both eyes, sometimes surrounding a blind spot, have also been described. Other symptoms, including numbness or weakness along one side, or speech disturbances, occur rarely.
Some people describe their visual symptoms of loss of vision, which lasts for less than an hour, and may or may not be associated with head pain once the vision returns, as an ocular migraine. These symptoms are also known as retinal migraine, and may be associated with symptoms similar to those described as an aura, such as blind spots, complete loss of vision in one eye, or flashing lights. If a patient experiences these symptoms regularly, evaluation to exclude a primary retinal problem is needed.
Eye pain which is different from sensitivity to light is not a common component of migraine. If eye pain is a persistent symptom, or if eye pain is present and accompanied by blurred vision or loss of vision, then prompt evaluation is recommended.
In comparison, a tension headache is described as being bilateral and the pain is not pulsating, but feels like pressure or tightness. While severity can be mild-to-moderate, the headache is not disabling and there is no worsening of the pain with routine physical activity; additionally, there is no associated nausea, vomiting, photophobia, or phonophobia.
No specific physical findings are found when patients are experiencing a routine migraine headache. If an abnormality is identified on physical examination, there should be suspicion of another cause for the headache.
How are migraines diagnosed?
According to the International Classification of Headache Disorders II (ICHD-II) criteria for migraine without aura, a patient must have had at least five headache attacks fulfilling the following criteria:
Headache attacks lasting 4 to 72 hours (untreated or unsuccessfully treated)
The headache has at least two of the following characteristics:
· Unilateral location
· Pulsating quality
· Moderate or severe pain intensity
· Aggravation by or causing avoidance of routine physical activity (for example, walking or climbing stairs)
During the headache, at least one of the following characteristics:
· Nausea and/or vomiting
· Photophobia and/or phonophobia
The headache cannot be attributed to another disorder
What is the treatment for migraines?
The treatment for migraines depends upon on how frequently the headaches occur and how long the headaches last.
The treatment of an acute migraine headache may vary from over-the-counter medicines (OTC), like acetaminophen (Tylenol and others), ibuprofen (Advil, Motrin, etc.), or naproxen sodium (Aleve) to prescription medications.
Triptans
Triptans (sumatriptan, rizatriptan, eletriptan, zolmitriptan, naratriptan, almotriptan, and frovatriptan), may be extremely effective in treating migraines and may be prescribed to help the patient treat their migraine at home. A combination of naproxen and sumatriptan is now available. Additionally, sumatriptan is now available as a patch which delivers the medication though the skin.
Not every patient can take these medications, and there are specific limitations regarding how often these medications can be used.
Other medication regimens may also be used to control migraine headache.
Some medications are appropriate for home use and others require a visit to the health-care professional's office or emergency department.
Other migraine treatments
Dihydroergotamine (DHE 45) can be administered intravenously or by nasal spray; this medication cannot be used if a triptan has been used within the preceding 24 hours.
Diclofenac potassium for oral solution (Cambia) is a potent anti-inflammatory medication recently approved for treatment of migraine.
Narcotics
Narcotic pain medications are not necessarily appropriate for the treatment of migraine headaches and are associated with the phenomenon of rebound headache, where the headache returns -- sometimes more intensely -- when the narcotics wear off. In all cases of migraine, the use of acute pain therapies must be watched closely so that a patient does not develop medication overuse headache.
Overuse of many of the medications used to treat migraine headache can lead to increased headache frequency, or even daily headaches. This type of headache phenomenon is known as medication overuse headache.
Other medications
If an individual experiences frequent headaches, or if the headaches routinely last for several days, then preventive medications may be indicated. These may be prescribed on a daily basis in an effort to decrease the frequency, severity, and duration of migraine headaches. There are many different medications which have been shown to be effective in this role, including:
Ø Blood pressure medications, for example, propranolol (Inderal), nadolol (Corgard), verapamil (Clan, Covera, Isoptin, Verelan), and flunarizine),
Ø anti-seizure medications, for example, divalproex sodium (Depakote and others),topiramate ( Topamax), and gabapentin (Neurontin, Gralise),
Ø antidepressant medications (amitriptyline and venlafaxine) and
Ø other supplements (magnesium, butterbur, and riboflavin).
The specific medication which is selected for a patient is dependent on many other factors, including age, sex, blood pressure, and other pre-existing medical conditions.
Some patients who experience more than 15 headache days every month might benefit from Botox injections.