Saturday, January 24, 2009

headache- preventive medicatin

Preventative medication may be prescribed for patients who have frequent migraine attacks (three or more a month), those who do not respond consistently to acute treatment, and when specific medicines are contraindicated because of other medical conditions (such as stroke or bleeding in the brain). Studies have reported that as many as 40% of these patients may benefit from preventative treatment. The U.S. Food and Drug Administration (FDA) has approved four prescription drugs for migraine prevention. These include the beta-blockers propranolol (Inderal®) and timolol (Blocadren®), and the anticonvulsants topiramate (Topamax®) and divalproex sodium (Depakote®).

Anticonvulsants: Anticonvulsant medicines, normally used for seizures, have been used to prevent migraine headaches. Examples of anticonvulsants that have been used are valproic acid (Depakote®, Depakote ER®, Depakene®), phenobarbital, gabapentin (Neurontin®), and topiramate (Topamax®). Control of the cortical spreading depression (CSD), is thought to be the reason for anticonvulsant effectiveness in preventing migraine attacks. Side effects include fatigue (tiredness), nausea, vomiting, and trembling.

Beta-blockers: Beta-blockers are a class of drugs that safely slow the heart beat and decrease blood pressure. Beta-blockers have been used for many years to prevent migraine headaches. In migraine prevention, beta-blockers help dilate (open) blood vessels in the brain, which may prevent the vascular (blood vessel) symptoms associated with a migraine attack, including vasoconstriction (blood vessel narrowing) and vasodilation (blood vessel widening). Beta-blockers can also help reduce physical symptoms associated with migraine attacks, such as anxiety, heart palpitations, and shaking,

Beta-blockers used in migraine prevention include propranolol (Inderal®), atenolol (Tenormin®), metoprolol (Lopressor®, Toprol XL®), and nadolol (Corgard®). Beta-blockers generally are well tolerated in most individuals. They can aggravate breathing difficulties in patients with asthma, chronic bronchitis (inflammation of the bronchial tubes), or emphysema (loss of lung function). In patients who already have slow heart rates (bradycardia) and heart block (defects in electrical conduction within the heart), beta-blockers can cause dangerously slow heartbeats. Beta-blockers can aggravate symptoms of heart failure. Other side effects include drowsiness, diarrhea, constipation, fatigue (tiredness), insomnia, nausea, depression, dreaming, memory loss, and impotence (loss of sexual performance).

Calcium channel blockers (CCBs): CCBs are a class of drugs normally used for high blood pressure, angina (chest pain), and arrhythmias (abnormal heart rhythms). CCBs also appear to alter serotonin (a brain chemical). Serotonin imbalances are a causative factor in developing a migraine. CCBs used in preventing migraine headaches are diltiazem (Cardizem®, Dilacor®, Tiazac®), and verapamil (Calan®, Verelan®, Isoptin®).The most common side effects of CCBs are constipation, nausea, headache, rash, edema (swelling of the legs with fluid), low blood pressure, drowsiness, and dizziness. Drinking grapefruit juice or eating grapefruit may cause levels of CCBs to rise, potentially leading to life threatening arrhythmias (irregular heart beats). Healthcare professionals recommend that individuals taking CCBs not consume grapefruit juice.

Hormone replacement therapy (HRT): For women with hormonal imbalances that may be causing the migraines, hormone replacement therapy (HRT) may be used, including estrogen and progesterone. HRT, however, may cause side effects such as blood clots, an increased risk of developing some types of cancers, and heart disease. Menstruating women at risk for migraines may be placed on oral contraceptives for HRT. Pre-pubescent girls that are at risk for migraine attacks will not be treated with HRT, but with other methods such as beta-blockers and anticonvulsants.

Lifestyle: Lifestyle changes, including decreasing stress levels, increasing exercise levels, and controlling the diet, have a major impact on migraine prevention and development. Lifestyle factors that are important in the prevention of migraines include regular sleep patterns, regular exercise (level depends upon the individual), limiting stress, limiting caffeine consumption to less than two caffeine-containing beverages a day, avoiding bright or flashing lights, and wearing sunglasses if sunlight is a trigger. Identifying and avoiding foods that trigger headaches is important. Healthcare professionals recommend keeping a food journal, where the individual writes down everything they have for each meal of the day. Then review the diary with a healthcare professional. It is impractical to adopt a diet that avoids all known migraine triggers; however, it is reasonable to avoid foods that consistently trigger migraine headaches. Triggers vary from one individual to another.

Tricyclic antidepressants (TCAs): TCAs are thought to prevent migraine headaches by altering the balance of serotonin, a neurotransmitter in the brain. Low levels of serotonin are thought to be a causative agent in migraine attacks. Chronic stress and depression can cause elevated levels of the stress hormone cortisol, which is produced in the adrenal glands. Cortisol can in turn cause imbalances in serotonin, leading to a migraine attack. The tricyclic antidepressants that have been used in preventing migraine headaches include amitriptyline (Elavil®), nortriptyline (Pamelor®, Aventyl®), doxepin (Sinequan®), and imipramine (Tofranil®). Side effects include constipation, dry mouth, low blood pressure (hypotension), increased heart rate, (tachycardia), urinary retention, sexual dysfunction, and weight gain. TCAs may cause excessive sedation and fatigue (tiredness).

Others: Other drugs less commonly used for migraine prevention include anti-serotonin medications, including methysergide (Sansert®), which prevent migraine headaches by constricting (making smaller) blood vessels and reducing inflammation of the blood vessels. Cyproheptadine (Periactin®) is an antihistamine that increases serotonin activity and is used occasionally in migraine prevention. Low levels of serotonin are a cause of migraine attacks.

Acute (Immediate):

Over-the-counter (OTC) treatments: The U.S. Food and Drug Administration (FDA) has approved three over-the-counter (OTC) products to treat migraine attacks. Excedrin® Migraine (a combination of aspirin, acetaminophen, and caffeine) is indicated for migraine and its associated symptoms such as head pain. Advil® Migraine and Motrin® Migraine Pain (both are ibuprofen) have anti-inflammatory action and are approved to treat migraine headache and its pain.

Triptans: The triptans attach to serotonin receptors on the blood vessels and nerves and thereby reduce inflammation and constrict (narrow) the blood vessels. A reduction in inflammation decreases pressure on nerves in the trigeminal nerve system (nerves in the cranium or head), which decreases the pain signals to the brain and stops the headache. Traditionally, triptans, which are prescription medicines, were prescribed for moderate or severe migraines after over-the-counter (OTC) analgesics such as ibuprofen (Advil®) 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 ten 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. Triptans include sumatriptan (Imitrex®), almotriptan (Axert®), naratriptan (Amerge®), rizatriptan (Maxalt®), zolmitriptan (Zomig®), frovatriptan (Frova®), and eletriptan (Relpax®).

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 (tiredness), and dizziness. These side effects are short-lived and are not considered serious. Triptans are not used in pregnant women and are not generally used in young children.

In patients with severe nausea, a combination of a triptan and an anti-nausea medication, such as prochlorperazine (Compazine®), may be used.

Ergots: Ergots, like triptans, are medications that abort migraine headaches. Examples of ergots include ergotamine preparations (Cafergot®) and dihydroergotamine preparations (Migranal®, DHE-45®). Ergots, like triptans, cause constriction (narrowing) 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 the produce more negative effects on the heart than the triptans. Therefore, the ergots are not as safe as the triptans. Ergots are used to help stop the vasodilation (blood vessel widening) associated with a migraine attack. 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). The combination medication can help take care of three potential factors associated with a migraine attack, including vasodilation, pain, and anxiety. Midrin® is most effective if used early during a headache. However, because of its potent blood vessel constricting effect, it should not be used in patients with high blood pressure, kidney disease, glaucoma (increased pressure in the eyes), atherosclerosis (hardening of the arteries), liver disease, or in patients taking monoamine oxidase inhibitors (MAOIs) including phenelzine (Nardil®), isocarboxazid (Marplan®), and tranylcypromine sulfate (Parnate®).

Other prescription medications: Some attacks may not be eliminated by acute therapy, and the individual requires pain-relieving measures. Due to the severity of the headaches, some patients may require a narcotic analgesic, including oxycodone (Percocet®), codeine, or meperidine (Demerol®). If the individual is experiencing frequent migraine attacks, the habitual use of opiate analgesics should be avoided. Opiates can cause addiction (both physical and mental) and may also cause rebound headaches, which are headaches that occur when the pain medicine no longer provides relief.

Butorphanol (Stadol NS®) is an opiate-like drug available for injection and intranasal (in the nose) administration. The normal dosage of Stadol NS® is one spray into the nostril, which usually relieves migraine symptoms in 15-30 minutes. This drug can be used every hour for relief. The use of Stadol NS® may result in dependency if used regularly for pain relief. Side effects include nausea and vomiting, nasal irritation, and sedation.

Butalbital, a barbiturate medication, is also used for the immediate relief of migraine headache pain. It is used in various prescription combinations with aspirin, acetaminophen, caffeine, or codeine (an opiate pain medication). These medications are potentially addicting and are not used as initial treatment. They are sometimes used for patients whose headaches fail to respond to over-the-counter (OTC) medications but who are not candidates for triptans either due to pregnancy or the risk of heart attack and stroke. Products include butalbital and acetaminophen (Axocet®, Bupap®, Cephadyn®, Phrenilin®, or Sedapap®); butalbital, acetaminophen, and caffeine (Fioricet®, Esgic®); butalbital and aspirin (Axotal®); butalbital, aspirin, and caffeine (Fiorinal®); butalbital, acetaminophen, caffeine, and codeine (Fioricet #3 with Codeine® or Fioricet w/ Codeine®); and butalbital, aspirin, caffeine, and codeine (Fiorinal #3 with Codeine® or Fiorinal w/ Codeine®).

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