A migraine headache is a form of vascular headache. Migraine headache is caused by a combination of vasodilatation (enlargement of blood vessels) and the release of chemicals from nerve fibers that coil around the blood vessels. During a migraine attack, the temporal artery enlarges. (The temporal artery is an artery that lies on the outside of the skull just under the skin of the temple.) Enlargement of the temporal artery stretches the nerves that coil around the artery and causes the nerves to release chemicals. The chemicals cause inflammation, pain, and further enlargement of the artery. The increasing enlargement of the artery magnifies the pain.
Migraine attacks commonly activate the sympathetic nervous system in the body. The sympathetic nervous system is often thought of as the part of the nervous system that controls primitive responses to stress and pain, the so-called "fight or flight" response. The increased sympathetic nervous activity in the intestine causes nausea, vomiting, and diarrhea. Sympathetic activity also delays emptying of the stomach into the small intestine and thereby prevents oral medications from entering the intestine and being absorbed. The impaired absorption of oral medications is a common reason for the ineffectiveness of medications taken to treat migraine headaches. The increased sympathetic activity also decreases the circulation of blood, and this leads to pallor of the skin as well as cold hands and feet. The increased sympathetic activity also contributes to the sensitivity to light and sound sensitivity as well as blurred vision.
Migraine afflicts 28 million Americans, with females suffering more frequently (17%) than males (6%). Missed work and lost productivity from migraine create a significant public burden. Nevertheless, migraine still remains largely undertreated and underdiagnosed. Less than half the sufferers are diagnosed by their doctors.
Medication therapies for migraine
Individuals with occasional mild migraine headaches that do not interfere with daily activities usually medicate themselves with over-the-counter (OTC, non-prescription) pain relievers (analgesics). Many OTC analgesics are available. OTC analgesics have been shown to be safe and effective for short-term relief of headache (as well as muscle aches, pains, menstrual cramps , and fever) when used according to the instructions on their labels.
There are two major classes of OTC analgesics: acetaminophen (Tylenol) and non-steroidal anti-inflammatory drugs (NSAIDs). The two types of NSAIDs are aspirin and non-aspirin. Examples of non-aspirin NSAIDs are ibuprofen (Advil, Nuprin, Motrin IB, and Medipren) and naproxen (Aleve). Some NSAIDs are available by prescription only. Prescription NSAIDs are usually prescribed to treat arthritis and other inflammatory conditions such as bursitis, tendonitis, etc. The difference between OTC and prescription NSAIDs may only be the amount of the active ingredient contained in each pill. For example, OTC naproxen (Aleve) contains 220 mg of naproxen per pill, whereas prescription naproxen (Naprosyn) contains 375 or 500 mg of naproxen per pill.
Acetaminophen reduces pain and fever by acting on pain centers in the brain. Acetaminophen is well tolerated and generally is considered easier on the stomach than NSAIDs. However, acetaminophen can cause severe liver damage in high (toxic) doses or if used on a regular basis over extended periods of time. In individuals who regularly consume moderate or large amounts of alcohol, acetaminophen can cause serious damage to the liver in lower doses that usually are not toxic. Acetaminophen also can damage the kidneys when taken in large doses. Therefore, acetaminophen should not be taken more frequently or in larger doses than recommended on the label. For information, please read the Acetaminophen and Liver Damage article.
NSAIDs relieve pain by reducing the inflammation that causes the pain (They are called non-steroidal anti-inflammatory drugs or NSAIDs because they are different from corticosteroids such as prednisone, prednisolone, and cortisone which also reduce inflammation). Corticosteroids, though valuable in reducing inflammation, have predictable and potentially serious side effects, especially when used long-term. NSAIDs do not have the same side effects that corticosteroids have.
Aspirin, Aleve, Motrin, and Advil all are NSAIDs and are similarly effective in relieving pain and fever. The main difference between aspirin and non-aspirin NSAIDs is their effect on platelets. Platelets are small particles in the blood that cause blood clots to form. Aspirin prevents the platelets from forming blood clots. Therefore, aspirin can increase bleeding by preventing blood from clotting though it also can be used therapeutically to prevent clots from causing heart attacks and strokes. The non-aspirin NSAIDs also have anti-platelet effects, but their anti-platelet action does not last as long as aspirin.Aspirin, acetaminophen, and caffeine also are available combined in OTC analgesics for the treatment of headaches. Examples of such combination analgesics are Pain-aid, Excedrin, Fioricet, and Fiorinal.
Finding an effective analgesic or analgesic combination often is a process of trial and error because individuals respond differently to different analgesics. In general, a person should use the analgesic that has worked in the past. This will increase the likelihood that an analgesic will be effective and decrease the risk of side effects.
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