Migraine-specific abortive medications usually are necessary for moderate to severe migraine headaches. The abortive medications for moderate or severe migraine headaches are different than OTC analgesics. Instead of relieving pain, they abort headaches by counteracting the cause of the headache, dilation of the temporal arteries. In fact, they cause narrowing of the arteries. Examples of migraine-specific abortive medications are the triptans and ergot preparations.
Triptans
The triptans attach to serotonin receptors on the blood vessels and nerves that surround them, constrict the blood vessels, and reduce the inflammation. This stops the headache. The triptan with the longest history of use is sumatriptan (Imitrex). Sumatriptan is available in the US as an injection, oral tablet, and nasal inhaler. Zolmitriptan (Zomig) and rizatriptan (Maxalt) are newer triptans that are available as oral tablets and as tablets that melt in the mouth. Naratriptan (Amerge), almotriptan (Axert) and frovatriptan (Frovalan) are available only as oral tablets.
Traditionally, triptans were prescribed for moderate or severe migraines after OTC analgesics and other simple measures failed. Newer studies suggest that triptans can be used as the first treatment for patients with migraines that are causing disability. (Significant disability is defined as more than 10 days of at least 50% disability during a three-month period.). Triptans should be used early after the migraine begins, before the onset of pain or when the pain is mild. Using a triptan early in an attack increases its effectiveness, reduces side effects, and decreases the chance of recurrence of another headache during the following 24 hours. Used early, triptans can be expected to abort more than 80% of migraine headaches within two hours.
The U.S. Food and Drug Administration (FDA) has issued a warning about taking triptans together with medications of the SSRI (selective serotonin reuptake inhibitor) or SNRI (selective serotonin/norepinephrine reuptake inhibitor) classes. Taking these medicines together can cause a serious condition called serotonin syndrome.
Side effects of triptans
The most common side effects of triptans are facial flushing, tingling of the skin, and a sense of tightness around the chest and throat. Other less common side effects include drowsiness, fatigue, and dizziness. These side effects are short-lived and are not considered serious.
The most serious side effects of triptans are heart attacks and strokes. Triptans are effective in migraine headaches because they narrow arteries in the head; however, they also can narrow arteries in the heart. In individuals without existing carotid or coronary artery disease, the narrowing caused by triptans usually does not cause problems. However, persons whose carotid and coronary arteries are narrowed by atherosclerosis or who suffer from intermittent spasm of the coronary arteries (a condition called Prinzmetal's or variant angina), the narrowing caused by triptans can further reduce the flow of blood through the arteries and have been reported to cause heart attacks and strokes. Therefore, triptans should not be used by those who have had heart attacks and strokes, or those who have symptoms of atherosclerosis such as angina, transient ischemic attack (TIAs), and intermittent claudication.
Healthy adults may have atherosclerosis and narrowing of the coronary arteries that are "silent", that is, without past strokes, transient ischemic attacks, heart attacks, or angina. Therefore, before prescribing a triptan, a doctor should evaluate patients for possible atherosclerosis if they have one or more risk factors for developing atherosclerosis. These risk factors include cigarette smoking, diabetes mellitus, high blood pressure, high levels of LDL ("bad") cholesterol in the blood, obesity, male and over 40 years of age, female and postmenopausal, or a family member(s) who has had heart attacks at an early age. Some patients who are at risk should receive their first dose of a triptan in the doctor's office while being monitored with an electrocardiogram (EKG).
Triptans can interact with other drugs. For example, there have been rare reports of triptans causing a "serotonin syndrome" when given together with a selective serotonin reuptake inhibitor. Selective serotonin reuptake inhibitors (SSRIs) are a class of medications widely used to treat depression. The symptoms of serotonin syndrome include confusion, fever, tremor, high blood pressure, diarrhea, and sweating. Certain triptans such as sumatriptan, zolmitriptan, and rizatriptan can interact with monoamine oxidase inhibitors. Propranolol (Inderal) can raise rizatriptan blood levels. Cimetidine (Tagamet) can increase zolmitriptan blood levels.
Triptans should not be used in pregnant women and are not generally used in young children.
Ergots
Ergots, like triptans, are medications that abort migraine headaches. These may be combined with caffeine and/or other pain relief medications in combination products. Examples of ergots include ergotamine preparations (Ergomar, Wigraine, and Cafergot) and dihydroergotamine preparations (Migranal, DHE-45). Ergots, like triptans, cause constriction of blood vessels, but ergots tend to cause more constriction of vessels in the heart and other parts of the body than the triptans, and their effects on the heart are more prolonged than those of the triptans. Therefore, they are not as safe as the triptans. The ergots also are more prone to cause nausea and vomiting than the triptans. The ergots can cause prolonged contraction of the uterus and miscarriages in pregnant women.
Midrin
Midrin is used to abort migraine and tension headaches. It is a combination of isometheptene (a blood vessel constrictor), acetaminophen (a pain reliever), and dichloralphenazone (a mild sedative). It is most effective if used early during a headache; however, because of its potent blood vessel constricting effect, it should not be used in persons with high blood pressure, kidney disease, glaucoma, atherosclerosis, liver disease, or taking monoamine oxidase inhibitors.
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