Headaches: What are they?
A headache is a condition of mild to severe pain in the head; sometimes upper back or neck pain may also be interpreted as a headache.
Headaches have a wide variety of causes, ranging from eyestrain to inflammation of the sinus cavities to life-threatening conditions such as encephalitis. When the headache occurs in conjunction with a head injury the cause is usually quite evident; however, many causes of headaches are more elusive. The most common type of headache is a tension headache. Some people experience headaches when they are hungry or dehydrated.
Types of Headache
Tension headaches, which were recently renamed tension type headaches by the International Headache Society, are the most common type of headaches. The pain can radiate from the neck, back, eyes, or other muscle groups in the body. Nearly everyone will have at least one tension headache in their lifetime.
Frequency and duration
Tension headaches can be episodic or chronic. Episodic tension headaches are defined as tension headaches occurring less than 15 days a month, whereas chronic tension headaches occur 15 days or more a month for at least 6 months. Tension headaches can last from minutes to days or even months, though a typical tension headache lasts 4-6 hours.
Tension headache pain is often described as a constant pressure, as if the head were being squeezed in a vise. The pain is frequently bilateral which means it is present on both sides of the head at once. Tension headache pain is typically mild to moderate, but may be severe. In contrast to migraine, the pain does not increase during exercise.
What causes these headaches
The exact cause of tension headaches is still unknown. It has long been believed that they are caused by muscle tension around the head and neck. However although muscle tension may be involved, there are many forms of tension headaches and some scientists now believe there is not one single cause for this type of headache. One of the theories is that the pain may be caused by a malfunctioning pain filter which is located in the brain stem. The view is that the brain misinterprets information, for example from the temporal muscle or other muscles, and interprets this signal as pain. One of the main molecules which is probably involved is serotonin. Evidence for this theory comes from the fact that tension headaches may be successfully treated with certain antidepressants. Another theory says that the main cause for tension type headaches and migraine is teeth clenching which causes a chronic contraction of the temporalis muscle.
Episodic tension headaches generally respond well to over-the-counter analgesics, such as acetaminophen or aspirin. However, these medications should be avoided in cases of chronic tension headache, due to the risk of rebound headaches. Chronic tension headaches are more difficult to treat. Suggested therapies include:
- Swimming two to three times a week
- Heat pillow
- The NTI Tension Suppression System
Relaxation techniques like:
- Jacobson's Progressive Muscle Relaxation
- Autogenous training
Tension headaches are exacerbated by states or activities that induce muscle tension, such as stress. Avoiding such states can lessen the frequency of tension headaches. Tension headaches can also be secondary to other conditions, such as an upper respiratory infection or other virus.
Often the best treatment for a mild tension headache that does not impair a person's ability to function is simple endurance. Many tension headache sufferers receive relief from sleep.
Migraine is a form of headache, usually very intense and disabling. It is a neurologic disease of vascular origin characterized by attacks of sharp pain involving (usually) one half of the skull and accompanied by nausea, vomiting, photophobia and occasionally visual (or rarely other) disturbances known as aura. The symptoms and their timing vary considerably among migraine suffers, and to a lesser extent from one migraine attack to the next.
In some cases, migraine can cause seizures such as a tonic-clonic seizure. Stroke symptoms (passing or permanent) are seen in very severe subtypes.
Migraine is often caused by the expansion of the blood vessels of the head and neck. Classical migraine (migraine with aura) is forerun by a group of symptoms called aura, whereas common migraine does not have any indicator for the impending headache. A few (perhaps fortunate) people actually get aura without migraine. Cluster headaches have similar symptoms, but tend to recur in minutes or hours, rather than days, and affect a different area of the face.
Migraine can accompany, in some cases, another type of headache called Tension headache.
Migraine often runs in families and starts in adolescence, although some research indicates that it can start in early childhood or even in utero. Migraine occurs more frequently in women than men, and is most common between ages 15-45, with the frequency of attacks declining with age in most cases.
Because their symptoms vary, an intense headache may be misdiagnosed as a Migraine by a layperson. Where possible, see a doctor to determine if the headaches are a symptom of something else.
Treatment focuses on three areas:
- Elimination of triggers
- Abortive drugs
- Preventive drugs
In many patients the incidence of migraine can be reduced through diet changes to avoid certain chemicals present in such foods as cheddar cheese and chocolate, and in most alcoholic beverages. Other triggers may be situational and can be avoided through lifestyle changes.
Many people have found that eliminating most tannins from their diet can substantially reduce their migraines. This can happen even if they have known triggers, such as time-of-the-month for women, certain weather patterns, or going hungry. Some of the foods containing tannins are regular tea, apple juice, orange-coloured cheese, many alcoholic drinks, many herbs and spices.
Until the introduction of sumatriptan (Imitrex®/Imigran®) around 1985, ergot derivatives (see ergoline) were the primary oral drugs available to stop a migraine once it was underway. Analgesics and caffeine were used to provide some relief, though they are not effective for most sufferers. Narcotic pain medications, and antipsychotic drugs such as thorazine and compazine, are effective but have debilitating side effects at the doses required to achieve control.
Ergotamine tablets, usually with caffeine, are sometimes used. Dihydroergotamine (DHE), which must be injected or inhaled, is also effective. These drugs can be used either as preventive or abortive therapy.
Imitrex (sumitriptan) and the related 5-hydroxytryptamine (serotonin) receptor agonists are now available and are the therapy of choice for severe migraine that is relatively infrequent. They are highly effective and have few side effects when used occasionally. Some members of this family of drugs are sumatriptan (Imitrex®, Imigran®), zolmitriptan (Zomig®), naratriptan (Amerge®), rizatriptan (Maxalt®), eletriptan (Relpax®) and frovatriptan (Frova®).
Evidence is accumulating that these drugs are effective because they constrict certain blood vessels in the brain. They do this by acting at serotonin receptors on nerve endings. This action leads to a decrease in the release of a peptide known as CGRP. In a migraine attack, this peptide is released and produces pain by dialating cerebral blood vessels.
These drugs are available by prescription only (U.S.). Many migraine sufferers do not use them only because they have not sought treatment from a physician.
For patients who suffer frequent, intractable and severe symptoms, preventive and prophylactic medications can be used. A large number of medications with varying modes of action can be used. Selection of a suitable medication for any particular patent is a matter of trial and error, since the effectiveness of individual medications varies widely from one patient to the next.
Beta blockers such as propranolol and atenolol are usually tried first. Antidepressants such as amitriptyline may be effective. Antispasmodic drugs are used less frequently. Sansert was effective in many cases, but has been withdrawn from the U.S. market.
Migraine sufferers usually develop their own coping mechanisms for intractable pain. A warm bath, or resting in a dark and silent room may be more helpful than any other medication for many patients.
Some migraine sufferers find relief through acupuncture which is usually used to help prevent headaches from developing. Sometimes acupuncture is used to relieve the pain of an active migraine headache.
Supplementation of Coenzyme Q10 has been found to have a beneficial effect on the condition of some sufferers of migraines.
The plant feverfew (Tanacetum parthenium) is a traditional herbal remedy believed to reduce the frequency of migraine attacks. Clinical trials have been carried out, and appear to confirm that the effect is genuine (though it does not completely prevent attacks).
According to a recent survey (http://nccam.nih.gov/news/2004/052704.htm), 3.1% of the adult American population (http://nccam.nih.gov/news/report.pdf p9) use complementary and alternative medicine to treat migraine and severe headache.
Cluster headaches are rare headaches that occur in groups or clusters. Cluster headache sufferers typically experience very severe headaches of a piercing quality near one eye or temple that last for between 15 minutes and three hours. Cluster headaches are frequency associated with drooping eyelids, red, watery eyes, and nasal congestion on the affected side of the face. The headaches are unilateral and occasionally change sides. The neck is often stiff or tender in association with cluster headaches, and jaw and teeth pain is sometimes reported.
In episodic cluster headache, these headaches occur once or more daily, often at the same times each day, for a period of several weeks, followed by a headache-free period lasting weeks, months, or even years. Approximately 10-15% of cluster headache sufferers are chronic; they can experience multiple headaches every day for years. Cluster headaches are occasionally referred to as "alarm clock headaches", as they can occur at night and wake a person from sleep. Other synonyms for cluster headache include Horton's syndrome and "suicide headaches" (a reference to the excruciating pain and resulting desperation).
Medically, cluster headaches are considered benign, but they are extremely painful and can be debilitating. The location and type of pain has been compared to a 'brain-freeze' headache from rapidly eating ice cream; this analogy is limited, but may offer some insight into the cluster headache experience. Persons who have experienced both cluster headaches and other painful conditions (childbirth, migraines) report that the pain of cluster headaches is far worse. During a cluster headache attack, a person often alternates between pacing and laying still. Sensitivity to light (seeking the dark) is more typical of a migraine, as is vomiting but they can be present in some sufferers of cluster headache.
Whereas other headaches, such as migraines occur more often in women, cluster headaches occur in men at a rate 2.5 to 3 times greater than in women. Between 1 and 4 people per thousand experience cluster headaches in the U.S. and Western Europe; statistics for other parts of the world are fragmentary. Latitude plays a role in the occurrence of cluster headaches, which are more common as one moves away from the equator towards the poles. It is believed that greater changes in day length are responsible for the increase.
While the immediate cause of pain is in the trigeminal nerve, the true cause(s) of cluster headache is complex and not fully understood. Among the most widely accepted theories is that cluster headaches are due to an abnormality in the hypothalamus. This can explain why cluster headaches frequently strike around the same time each day, and during a particular season, as one of the functions the hypothalamus performs is regulation of the biological clock. Certain immune dysfunctions and metabolic abnormalities have also been reported in patients. There is a genetic component to cluster headaches, although no single gene has been identified as the cause. As a group, cluster headache patients are more likely to have suffered brain trauma than the general population. Sinus problems, damage to the jaw, and sleep apnea are also more common in cluster headache patients, but these factors do not adequately explain the disease.
Many doctors are unfamiliar with this disease, and cluster headaches often go undiagnosed for many years. Paroxysmal Hemicrania (PH) is a condition similar to cluster headache, but PH responds well to treatment with the anti-inflammitory drug indomethacin and the attacks are very much shorter, often lasting seconds only.
Over the counter pain medications (such as aspirin, acetaminophen, and ibuprofen) have no effect on the pain from a cluster headache. Some have reported partial relief from narcotic pain killers, but the frequency of their use in a cluster cycle (1-3 times a day) often disqualifies them from use. However, some newer medications like fentanyl have shown great promise in early studies and use.
Medications to treat cluster headaches are classified as either abortives or prophylactics (preventatives). The most successful abortives include breathing pure oxygen (12-15 liters per minute in a non-rebreathing apparatus) and triptan drugs like sumitriptan and zolmitriptan. A wide variety of prophylactic medicines are in use, and patient response to these is highly variable. Preventitives include muscle relaxants, lithium, calcium channel blockers such as Verapimil, ergot compounds, anti-seizure medicines, and atypical anti-psychotics.
Magnesium supplements have been shown to be of some benefit in about 40% of patients. Melatonin has also been reported to help some. Hot showers have helped about 15% of people who try it. Feverfew, a herb used to treat migraine, is not clearly beneficial according to anecdotes from web forums.
Suggestions that psilocybin (mushrooms) and LSD may be able to abort cluster cycles have not yet received any scientific proof and should be taken with extreme care and skepticism.
Some people with extreme headaches of this nature (especially if they are not unilateral) may actually have something else: an ictal headache. Anti-convulsant medications can significantly improve this condition, so make sure you talk with your doctor about this possibility if you think you might be affected.
Rebound headaches occur when medication is taken too frequently to relieve headache pain. Rebound headaches frequently occur daily and can be very painful. A diagnosis of rebound headaches can be easy or difficult, as the cause is very easy to identify but very difficult to diagnose. Overuse of painkillers can be confirmed simply by asking the patient if his or her headaches assumed a new pattern or became more severe after taking painkillers excessively (generally classified as more than 3 times per week). However, the only way to make a certain diagnosis of rebound headache is to withdraw the patient from medication for anywhere up to 6 months. It should be noted that withdrawal from medication will actually intensify the headaches for the first few weeks. After this period, the headaches will gradually recede.
Following treatment, many patients revert to their prior headache pattern. A physician should be consulted before re-use of medications.
Ice cream headache
Brain Freeze or ice cream headache is a term used to refer to the pain sometimes inflicted by devouring something cold like ice cream or a cold beverage, often very quickly.
The reaction is (obviously) triggered by the cold ice cream or beverage; coming into contact with the roof of the mouth. It triggers nerves that give the brain the impression of a very cold environment. To heat up the brain again, blood vessels start to swell, which causes the headache-like pain for approximately 30 seconds.
The temperature change in the roof of the mouth has to be rather drastic; this is why brain freeze often occurs on warm days.
The pain can be relieved by putting the tongue to the roof of the mouth, which logically will heat it up.
Ictal headaches are headaches associated with seizure activity. They may occur either before (pre-ictal), after (post-ictal), or most rarely during a seizure. Many cases of ictal headache may be misdiagnosed as migraine with aura, or even cluster headache. However, whereas these conditions usually involve just one side of the head (are unilateral), an ictal headache may be centrally situated or cover the entirety of the head.
Severity of ictal headaches can vary from a slight pressure or "cloud" to an intensity far beyond migraine. Some have called it a "suicide headache" in the worst instances. Temporary blindness may also occur in some cases.
Ictal headaches can be controlled with anti-convulsant medications, in many cases.
Note that other symptoms besides headache may be either present or absent, and may include unusual thoughts or experiences. In these cases it is especially important to obtain a correct diagnosis. Many people with these experiences are accidentally diagnosed with conditions such as psychosis or even schizophrenia and given anti-psychotic medications which ironically may increase seizure activity. An EEG is recommended to detect other signs of epilepsy in all cases, however even when this does not prove determinative, anti-convulsants may be a first line of treatment if these symptoms are present with headache.