Introduction
Do you have chronic headaches? You are not alone -- the National Headache Foundation estimates that about 45 million Americans suffer from recurring headaches. Many different types of headaches have many different causes, however, and individuals respond differently to treatment options, which range from meditation to drug therapy. Trying to find the best treatment is no simple matter. Patience and the willingness to try several different methods may be necessary to find what works best for you.
What is it?Tension Headache
The most common type of headache, tension headache pain is usually described as feeling like a tight band that puts constant pressure on both sides of the head. Pain may extend into the neck or shoulders. Generally, tension headaches are mild to moderate in severity and they do not usually interfere with routine activity. An occasional inconvenience for most individuals, tension headaches often have a specific cause such as fatigue or stress. However, some individuals may have frequent or even daily tension headaches that may be severe enough to limit regular activity. Chronic tension headaches may have no apparent cause or they may be associated with other conditions such as anxiety, depression, or insomnia. About equal numbers of men and women have tension headaches and individuals of any age may experience them, although they most commonly occur between the ages of 20 and 40 years.
Migraine Headache
Migraine headaches are often described as intense throbbing or pounding pain on one or both sides of the head. Nausea and the inability to tolerate light, smells, or sounds may accompany the pain of a migraine. Up to a third of individuals who have migraines may have a warning(or ?aura?) that a migraine is about to start. These individuals may experience an aura that may include visual changes (such as dimmed or blinking lights) or unusual sensations (such as tingling in their hands, feet, or face). Generally, migraines are infrequent, although they may be chronic for some individuals. Migraines can last for days, often leaving patients feeling exhausted and lethargic(lacking energy). While the exact causes of migraine headaches are unknown, individuals who have recurring migraines may be able to identify physical factors that ?trigger? their migraines. For example, some migraines are attributed to stress; others may occur in response to environmental changes, such as very cold weather; certain foods may contribute to other migraines. About three times as many women as men suffer from migraines, with many women experiencing migraines around their menstrual periods.
Cluster Headache
Much less common than migraines or tension headaches, cluster headaches usually occur in groups (clusters) that may continue for a few days up to several weeks. Most often cluster headaches involve sudden attacks of extreme pain lasting from a few minutes to several hours and often involving only one side of the head. Affecting many more men than women, cluster headaches may be associated with irritation of the eye and nose. Individuals who smoke and drink alcohol may be more prone to having cluster headaches. This type of headache is more common in people who have the following: eye problems, runny noses, or facial sweating.
Other Types of Headaches
Organic Headache
Organic headaches are relatively rare, but they need immediate medical attention because they have serious physical causes such as blood clots, brain tumors, brain infections, or bleeding into the brain. Sometimes becoming intensely severe over a few hours or days, they may be associated with weakness, confusion, or unconsciousness.
Sinus Headache
Usually, sinus headache pain is due to swelling in the sinus cavities around the nose and eyes. Often caused by allergies or infections, sinus headaches may be accompanied by fever, a stuffy nose, or toothaches. Leaning forward or lying down may increase sinus headache pain.
Rebound Headache
Ironically, rebound headaches result from overuse of headache medications. Individuals who take more headache medication than recommended, take it continually for long periods of time, or consume large amounts of caffeine may need more and more medication to control headache pain. When the effects of the medication start to decrease, the headache is even worse and more medication is needed. Eventually, the medication doesn?t work anymore. Individuals who have ten or more headaches a month may be experiencing rebound headaches.
Hormonal Headache
Headaches of the hormonal type often result from fluctuation of hormones in the female body, especially in relation to the menstrual cycle.
What causes it?
Almost all headaches involve changes in the nerves and blood vessels of the head. For many years, the narrowing and widening of blood vessels was believed to cause headaches, but recent evidence does not support that theory totally. Another popular theory is that severe headaches and other types of chronic pain may be associated with low levels of brain chemicals known as endorphins. Produced in the pituitary and hypothalamus glands, endorphins are known to play roles in regulating pain.
Many headaches have no identifiable triggers (something that makes the headache start), but others may be associated with certain physical or emotional factors. Headache triggers are many and varied.
Physical factors such as prolonged sitting in an uncomfortable position may prompt a tension headache for some individuals. Other tension headaches may result from dust, noise, or poor lighting. Emotional issues, including anger, depression, and grief, may also contribute to tension headaches.
Several triggers have been identified for migraines. They include hormonal changes, stress, caffeine, poor diet, light, alcohol, smoking, lack of sleep, or illness.
Cluster headaches may be started by drinking alcohol, being exposed to glaring lights, experiencing heat or cold, or eating certain foods such as citrus fruits or chocolate. Food additives such as monosodium glutamate (MSG commonly found in Chinese foods) and aspartame (an artificial sweetener) may bring on headaches for some individuals. Some medications -- including both prescription and over-the-counter medications that are used to treat headaches -- can actually cause headaches, if they are taken improperly.
Sinus headaches represent a common example of headaches that result from a specific condition. Brain abnormalities (such as meningitis an infection in the brain or spinal chord, blood clots, or brain tumors) are examples of rare, but extremely dangerous illnesses that may also produce headache pain.
Who has it?
Headaches are among the most common complaints that health care practitioners encounter. Up to 90% of the population of the United States will have at least one headache per year, with an estimated 45 million Americans suffering chronically from headaches. Migraines also have had an impact economically due to the increasing cost of the medications for their treatments.
What are the risk factors?
Risk factors are characteristics that may make individuals more likely to develop a condition. Common risk factors for headaches include the following:
- Tension Headache
- Female gender
- Migraine Headache
- Female gender
- Family history
- Less advantaged socioeconomic groups
- Cluster Headache
- Male gender
- Rebound Headache
- Overuse of headache medicines
Tension Headache
Almost 90% of tension headaches result from tightness in the scalp and neck. The pain of a tension headache is usually described as a constant pressure that feels like a vise or a tight band squeezing on both sides of the head. Pain may spread to the scalp, face, neck, and shoulders. Often the neck or shoulder muscles tighten, giving this type of headache the alternate name of muscle contraction headache. Not usually associated with additional symptoms, tension headaches are classified according to frequency. Chronic tension headaches occur daily or almost every day. Tension headaches that occur only a few times a year are called episodic tension headaches.
Migraine Headache
Migraine headaches are characterized as intense pounding pain, which may affect one or both sides of the head lasting anywhere from 4 to 72 hours. The two main forms of migraine are:
- Migraine with Aura (formerly called classic migraine) An aura is a neurological (meaning, related to the nervous system) disturbance experienced by about one-fourth to one-third of all individuals who have migraines. About 10% of all migraine sufferers will have an aura on a consistent basis. Usually consisting of visual changes that may include seeing colored or flashing lights or squiggly lines, an aura may also involve physical symptoms such as numbness or tingling sensations in the face, fingers, or toes. Some individuals may experience temporary or loss of vision when experiencing a pre-migraine aura. Typically, an aura begins approximately 10 to 30 minutes before the onset of the headache.
- Migraine without Aura (formerly called common migraine). Individuals with this type of migraine have little or no warning that a migraine is about to occur.
Other symptoms that may be associated with migraines include:
- Cold, clammy, or sweaty skin
- Confusion
- Fatigue
- Depressed mood
- Fluid retention
- Muscle pain
- Food cravings
- Numbness or a sensation of pins and needles
- Inability to tolerate light, noise, or smells
- Light-headedness
- Nausea
- Vomiting
Cluster Headache
Cluster headaches generally start suddenly and they often affect only one side of the head. A single cluster headache is usually brief lasting from a few minutes to about 4 hours, then decreasing or disappearing. Occurring repeatedly at roughly the same times of day, however, cluster headaches typically extend over a period of 4 to 12 weeks, followed by a period of remission. This on and off sequence may last for a few months or it may occur chronically over many years. Other symptoms of a cluster headache may include nasal congestion, facial sweating, runny nose, drooping eyelids, and irritated, teary eyes. Men are 4 to 7 times more likely to suffer from cluster headaches than women.
Other Headaches
Organic Headache
An organic or secondary headache is the result of a brain tumor, a brain infection, bleeding into the brain, or other severe illness. Accounting for less than 5% of all headaches, organic headaches may occur as sudden, sharp, extremely severe pain. Symptoms that frequently accompany organic headaches may include confusion, seizures, sudden loss of balance, or difficulty with speech. Because organic headaches are indications of a more serious illness, individuals experiencing any of these symptoms should receive emergency medical care.
Sinus Headache
Sinus headache pain usually results from pressure exerted by swollen, inflamed tissue in sinus passages. Generally, due to infections, sinus headache pain is localized in the forehead, above the cheekbones, and behind the bridge of the nose. Pain, which may vary from dull aches to moderately intense pain, may extend to the teeth or jaw. Other symptoms of a sinus headache may include:
- Chills
- Fever
- Greenish or yellow nasal secretions
- Nasal congestion
- Swollen face
Rebound Headache
Taking headache medications on a regular basis may create a need to increase the dose for the medication to be effective. As the dose increases, the headache pain may get worse, and the dose may need to be increased even more. The medication (or doses of it that are no longer strong enough) actually may begin to cause a headache.
Hormonal Headache
Changes in estrogen levels due to menstrual periods may trigger headaches for some women. Usually beginning a few days before the start of a menstrual period, hormonal headaches may be associated with other symptoms of premenstrual syndrome (PMS) such as bloating, breast tenderness, fatigue, irritability, and joint pain. Pregnancy, menopause, or oral contraceptive use may also cause hormonal fluctuations that may lead to headaches.
How is it treated?
Appropriate treatment for headaches is highly specialized depending on the type of headache, individual response to therapy, and any associated health conditions the person may also have. Lifestyle changes may be enough to resolve some headaches. For example, avoiding the foods that are known to trigger migraines may prevent migraine occurrence for certain individuals. In addition, numerous prescription and non-prescription medications are available treat and prevent headaches. Several medications or combinations of medications may have to be tried to find the best treatment.
In general, medications for headaches focus on two areas:
- Abortive therapy -- to stop a headache that has already started, and
- Prophylactic or preventive therapy -- to keep headaches from occurring.
Treatment Options
- Cluster Headache
Non-prescription drugs typically do not relieve cluster headaches. Therefore, treatment usually requires a prescription medication taken under a doctor's supervision.
Abortive therapy
The drugs of choice for cluster headache are oxygen and sumatriptan. These can either be given alone, or in combination. Inhaling pure oxygen may provide almost immediate relief for up to 80% of cluster headache attacks. Other initial treatment choices include prescription medications -- ergot derivatives or a triptan. For rapid relief of a cluster headache, an ergot derivative in a dosage form that is either quickly dissolved under the tongue (Ergomar), or injected (dihydroergotamine mesylate, DHE-45) is the second choice. Injected sumatriptan (Imitrex) may also be an effective treatment for cluster headaches in patients that don't respond well to oxygen and sumatriptan. Zolmitriptan (Zomig) may be considered over sumatriptan when given orally because 60% of patients experience relief at 30 minutes whereas sumatriptan may take longer to deliver relief.
Prophylactic/Preventive therapy
Calcium channel blockers, such as verapamil (Calan, Isoptin, Verelan) and diltiazem (Cardizem, Cartia, Dilacor, Diltia, Taztia, Tiazac), are also commonly used to prevent cluster headaches. Generally well tolerated, calcium channel blockers may cause constipation or swelling in the legs for some individuals who take them. Another well-tolerated medication is indomethacin, the only NSAID shown to be effective in preventing chronic cluster headaches. Possible side effects of indomethacin include dizziness, rash, stomach upset, and loss of appetite. The choice to begin taking indomethacin regularly should be carefully considered by a physician. Continued use of NSAIDs may lead to severe stomach irritation and result in ulcers (which must then be treated with more medications). Also patients with high blood pressure, heart failure, and kidney disease should know that taking NSAIDs may worsen these conditions. Always consult a physician before beginning long-term use of NSAIDs.
Other prescription medications that may be used to prevent cluster headaches may have more serious side effects, so they usually require close monitoring by a healthcare provider. Corticosteroids, such as prednisone (Deltasone, Orasone), may work well for preventing both episodic and chronic cluster headaches. They may cause insomnia, mood changes, upset stomach, and weight gain, however; and long-term therapy can affect thyroid function, cholesterol levels, blood pressure, and blood sugar levels.
Two other drugs used to treat cluster headaches are methysergide maleate (Sansert) and lithium (Eskalith, Lithobid). Methysergide maleate has been discontinued in the United States, but it may be available in other countries. Side effects from either methysergide maleate or lithium can be significant and treatment with either of them needs to be monitored closely by a healthcare provider.
- Organic Headache
Because organic headaches are caused by serious illnesses, any individual experiencing an unusually sudden or extremely severe headache should seek medical attention as soon as possible. Headaches that are accompanied by vision disturbances, numbness and/or weakness on one side of the body may be emergencies that also need immediate attention. Treatment may not be possible for organic headaches, but the condition causing the pain may be treatable.
- Tension Headache
Many different medication options are available for tension headaches. Ideal treatment for tension headaches is the medication that is most effective at the lowest dose and has the fewest potential side effects. If headaches are not relieved, the dose may be increased or another type of drug can be tried.
Abortive Therapy
Initial abortive therapies for tension headaches include non-prescription pain medications (also called analgesics) such as aspirin and acetaminophen (Tylenol). Usually medications like these are well tolerated, although some individuals may experience upset stomach when taking aspirin. Continually taking non-prescription analgesics daily for more than 2 weeks or taking higher than recommended doses can lead to rebound headaches. If an analgesic is being used with increasing frequency and less relief is occurring, other treatment options should be tried.
When aspirin or acetaminophen is not effective, a non-steroidal anti-inflammatory drug (NSAID) such as ibuprofen (Advil, Motrin) or naproxen (Aleve, Naprosyn) is usually the next step for pain relief. Some NSAIDs are available both without a prescription (usually in lower doses) and with a prescription (usually in higher doses). Common side effects include stomach irritation, which may be minimized if the medication is taken with food. Because individuals with kidney problems may be at increased risk for side effects, they should not begin taking an NSAID before discussing its use with a healthcare provider.
Other prescription treatments include muscle relaxants, such as carisoprodol (Soma) and cyclobenzaprine (Flexeril), and certain antidepressants (however, there is no evidence to support the effectiveness of these agents as abortive therapy). Both of these types of medications may cause drowsiness, however. A combination medication that includes isometheptene mucate, dichloralphenazone, and acetaminophen (Midrin, Duradrin) may also be used as abortive treatment for tension headaches. Caution should be used if it is taken because it may be habit-forming.
Prophylactic/Preventive Therapy
To prevent tension headaches, many different antidepressants may be effective for individuals with and without depressive symptoms. The antidepressant needs to be taken continually. Side effects depend on the individual drug, but they are usually mild. They may include constipation, dizziness, drowsiness, dry mouth, nausea, and weight gain.
In the case of tension headaches, psychophysiologic therapies such as stress management, relaxation training and biofeedback training may significantly reduce headache activity.
- Migraine Headache
Abortive Therapy
Initial abortive therapy for mild to moderate migraine headaches includes non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen (Advil or Motrin) and naproxen (Aleve or Naprosyn), and other non-prescription pain medications (also known as analgesics) such as aspirin and acetaminophen (Tylenol). Another medication available, without a prescription, that some find effective is a combination of aspirin, acetaminophen, and caffeine (Exedrine or Exedrine Migraine).
If non-prescription medications are not effective, several prescription medications are available to relieve migraines. Among the most commonly prescribed are selective serotonin agonists, commonly known as "triptans". Designed specifically for migraine treatment, seven triptans are available in the United States. They are almotriptan (Axert), eletriptan (Relpax), frovatriptan (Frova), naratriptan (Amerge), rizatriptan (Maxalt), sumatriptan (Imitrex), and zolmitriptan (Zomig). Triptans are generally prescribed for moderate to severe migraines with or without auras, and they also may work when other previous treatments have failed. They come in several different dosage forms that may include injections and nasal spray, as well as traditional tablets to take by mouth. In addition, rizatriptan and zolmitriptan are available in rapidly-dissolving tablets that melt quickly for fast absorption when placed on the tongue. Although triptans work in similar ways, one may be more effective than another for certain individuals. Therefore, individuals who do not find relief from one triptan may want to consider trying another triptan before switching to a completely different drug class. Triptans should not be used by individuals with heart disease or uncontrolled high blood pressure. And, as with other headache medications, overuse of triptans may lead to rebound headaches.
Ergot derivatives are a second-line prescription option for treating moderate to severe migraine headaches that do not respond to non-prescription treatment or triptans. Ergot derivatives are most effective in dosage forms that reach the bloodstream quickly. Sublingual tablets that dissolve quickly under the tongue (Ergomar), injections (dihydroergotamine mesylate, DHE-45), and nasal sprays (dihydroergotamine, Migranal) are rapidly-acting ergot derivatives. Although they are effective for many individuals, taking ergot derivatives usually requires close monitoring by a healthcare provider. They may be habit-forming and they may cause numerous side effects, including abdominal cramps, dizziness, dry mouth, and nausea. Individuals who experience potentially serious side effects such as leg cramps or coldness, numbness or pain in the hands or feet while taking an ergot derivative should contact a doctor immediately.
Combinations of isometheptene mucate, dichloralphenazone, and acetaminophen (Midrin, Duradrin) or combinations of aspirin or acetaminophen with butalbital, codeine, or both (Fiorinal, Fioricet) may also be used as abortive treatment for migraine headaches. Caution should be used because of the potential for dependence associated with these drugs.
Many individuals who suffer from migraines also have nausea, and some evidence suggests that stomach contents are poorly absorbed into the body during a migraine attack. Consequently, taking medications by mouth may not be as effective as using other routes of administration, such as rectal suppositories or injected medications.
Prophylactic/Preventive Therapy
One possible way to prevent migraines is to avoid triggers. Eating regular, healthy meals, limiting caffeine, eliminating other food triggers, and getting plenty of exercise may help to prevent migraines from occurring. Keeping a headache diary may facilitate identification of triggers (see the Helping Yourself section to learn more about headache diaries). If medication is needed, it usually has to be taken regularly. Only certain individuals are candidates for prophylactic therapy with medication. These are individuals whose migraines cause severe disruptions in normal activity despite treatment, and those who have frequent migraines requiring prescription medication (at least twice weekly) which puts them at risk for developing rebound headaches. For these persons, several prescription options are available.
Tricyclic antidepressants (TCAs), such as amitriptyline, may be effective migraine prevention for some individuals, especially those with underlying depression, insomnia, or tension headaches. Although amitriptyline is generally accepted to be the most effective TCA for prevention of headaches, other TCAs such as doxepin (Sinequan), imipramine (Tofranil), nortriptyline (Pamelor), and protriptyline (Vivactil) have also shown some effectiveness. TCAs should be taken at night because they can cause sedation. Other possible side effects from TCAs may include an unpleasant taste in the mouth, and dry eyes, mouth, and skin. Individuals with glaucoma or an enlarged prostate should use caution when taking TCAs due to the increased risk of side effects.
Other prescription medications commonly used for migraine prevention include oral beta-blockers, such as atenolol (Tenormin), metoprolol (Lopressor), propranolol (Inderal), and timolol (Blocadren); and calcium channel blockers, such as verapamil (Calan, Isoptin, Verelan). Common side effects of beta-blockers may include decreased blood pressure, depression, impotence, and lethargy. Common side effects of calcium channel blockers are decreased blood pressure, constipation, and leg swelling.
Some medications used primarily to treat epilepsy may also decrease the frequency, duration, and/or severity of migraine headaches. Valproic acid (Depakene), divalproex sodium (Depakote), and topiramate (Topamax) are anti-epileptics that are also approved for migraine prophylaxis. Tremor, weight gain, and hair loss are common side effects of these drugs. Rarely, they may cause liver damage. Therefore, symptoms of nausea, vomiting, and yellowing of eyes or skin should be brought to the attention of a doctor immediately. To decrease the risk of liver damage, blood tests should be performed periodically as long as anti-epileptic medications are taken.
Another drug occasionally used to prevent migraine headaches is methysergide maleate (Sansert). Methysergide maleate has been discontinued in the United States, but it may still be available in other countries. Its use must be limited due to the relatively high number of side effects that are associated with taking it. Dizziness, drowsiness, flushing, heartburn, insomnia, and stomach upset may all be caused by methysergide maleate. Long-term use may result in heart or lung changes. Methysergide maleate should be taken no longer than 6 months at a time, doses should be decreased gradually, and at least 3 to 4 weeks must be allowed before starting it again. Individuals taking methysergide maleate need to be supervised closely by a healthcare professional that is familiar with its use.
Non-drug Therapy
Resting in a cool, dark, quiet room is effective treatment for some migraine sufferers. Others find relief from an ice pack or cool water on their foreheads.
- Rebound Headache
The best way to treat headaches that result from taking too much headache medication is to stop the medication. Some individuals may stop all at once, while others need to stop more gradually. A health professional may need to determine the best way for each individual to stop over-using headache medication. Additional treatments for rebound headaches may include behavior modification therapy and the use of non-analgesic medications to help control headache pain until the headache medications are stopped.
- Sinus Headache
Since sinus headaches generally result from a sinus condition, the best approach is to treat that underlying condition. Non-prescription medications for sinus headaches commonly contain a pain reliever such as acetaminophen, as well as antihistamines for allergic conditions and/or decongestants for nasal congestion. If sinus pressure and pain is not relieved after a day or two of treatment with a non-prescription product, an infection may be present. A prescription antibiotic may be needed to treat a bacterial infection. If the sinus infection is caused by a virus, however, antibiotics will not be effective.
- Hormonal Headache
Hormonal headaches may be triggered by hormonal changes in the body. Most usually occurring as women begin their periods each month, hormonal changes also occur as young girls reach puberty, as women become pregnant, and as older women reach menopause. Taking oral contraceptives (birth control pills) may also cause hormonal headaches for some women – especially when the pills are first started.
Women who have hormonal headaches may start headache medication about 2 days before the period starts and continue taking the headache medication until the period has ended. Commonly effective headache medications include non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil, Motrin) and naproxen (Aleve, Naprosyn). Prescription treatment options may have more serious side effects that require close monitoring by a healthcare provider. These medications should be used only if NSAIDs do not provide adequate relief. Ergot derivatives in oral tablets or suppositories can be used; however, individuals should be aware that ergot derivatives might be habit forming. Their common side effects include abdominal cramping, nausea, dizziness, and dry mouth. Patients should report muscle pains, numbness, coldness, or loss of color in their hands or feet to their physician immediately. Methysergide maleate (Sansert) was another potential treatment. However, methysergide mesylate has been discontinued for sale in the United States. While it may still be available in other countries, its side effects can be significant. If methysergide maleate is taken, its use must be supervised closely by a doctor who is familiar with its use.
Drug classes used to treat Headache
- Ergot Derivatives
- Miscellaneous Analgesics and Antipyretics
- Narcotic Combinations
- Non-steroidal Anti-inflammatory drugs
- Salicylates
- Serotonin Receptor Agonists (Triptans)
While headaches are not unbearable for most individuals, research on potential headache treatments will continue to be very active simply because so many individuals do have occasional headaches. The resulting loss of productivity reaches several million hours per year. Both medications and non-medication treatments are under study.
Recently, the National Headache Foundation announced clinical trials evaluating current headache medicines being delivered in potentially more efficient ways - such as through the skin, nasal passages, or even the lungs. The following are some new delivery methods of headache medications that are currently being studied:
- The skin patch, Actyve(TM) by Vyteris, will release zolmitriptan by low electrical energy in the patch.
- DHE Nasal Powder by Britannia Pharmaceuticals with Novartis Pharmaceuticals, sprays powdered dihydroergotamine into the sinuses for faster absorption.
- Nasal capsaicin spray is proposed to help block the brain from knowing that there is pain. Capsaicin is usually found in topical creams over the counter to help with pain from cuts, scratches, burns, and other minor skin injuries that are causing discomfort.
- Another type of inhalation device using heat propels the drug prochlorperazine into the lungs for a faster rate of absorption into the body.
- Maybe the most interesting new medical idea is the carbon dioxide inhaler to be used for sinus headaches. This device will send carbon dioxide gas into one nostril simply to open up the nasal passageway.
Other medications that currently treat health conditions not associated with migraines are now being looked at to help relieve headaches. Some of these are oxcarbazepine, doxepin, donepezil, diclofenac, potassium, propofol injections, and calcitonin.
There is also a new migraine research study focusing on implanting a medical device into the migraine sufferer and stimulating major nerves thought to be associated with headache. Precision(TM), Genesis(TM), Medronic Synergy(TM), etc. are a few of the devices, some of these have been approved for other pain conditions however, none has been approved for treating migraines.
Finally, an experimental technique called thermography, which is used for diagnosing headache, is another area of intense investigation. In thermography, an infrared camera converts skin temperature into a color picture, or thermogram, with different degrees of heat appearing as different colors. Researchers have found that thermograms of headache patients show heat patterns that differ from those of people who never or rarely get headaches. Ways to change heat patterns may help to relieve headaches.
