A headache or cephalalgia is pain anywhere in the region of the head or neck. It can be a symptom of a number of different conditions of the head and neck. The brain tissue itself is not sensitive to pain because it lacks pain receptors. Rather, the pain is caused by disturbance of the pain-sensitive structures around the brain. Nine areas of the head and neck have these pain-sensitive structures, which are the cranium (the periosteum of the skull), muscles, nerves, arteries and veins, subcutaneous tissues, eyes, ears, sinuses and mucous membranes. ( Tramadol & Fioricet )
There are a number of different classification systems for headaches. The most well-recognized is that of the International Headache Society. Headache is a non-specific symptom, which means that it has many possible causes. Treatment of a headache depends on the underlying etiology or cause, but commonly involves analgesics. ( Tramadol & Fioricet )
Cause
There are over 200 types of headache, and the causes range from harmless to life-threatening. The description of the headache, together with findings on neurological examination, determines the need for any further investigations and the most appropriate treatment. ( Tramadol & Fioricet )
Primary headaches
The most common types of headache are the "primary headache disorders", such as tension-type headache and migraine. They have typical features; migraine, for example, tends to be pulsating in character, affecting one side of the head, associated with nausea, disabling in severity, and usually lasts between 3 hours and 3 days. Rarer primary headache disorders are trigeminal neuralgia (a shooting face pain), cluster headache (severe pains that occur together in bouts), and hemicrania continua (a continuous headache on one side of the head).
Secondary headaches
Headaches may be caused by problems elsewhere in the head or neck. Some of these are not harmful, such as cervicogenic headache (pain arising from the neck muscles). Medication overuse headache may occur in those using excessive painkillers for headaches, paradoxically causing worsening headaches. ( Tramadol & Fioricet )
A number of characteristics make it more likely that the headache is due to potentially dangerous secondary causes; some of these may be life-threatening or cause long-term damage. A number of "red flag" symptoms therefore means that a headache warrants further investigations, usually by a specialist. The red flag symptoms are a new or different headache in someone over 50 years old, headache that develops within minutes (thunderclap headache), inability to move a limb or abnormalities on neurological examination, mental confusion, being woken by headache, headache that worsens with changing posture, headache worsened by exertion or Valsalva manoeuvre (coughing, straining), visual loss or visual abnormalities, jaw claudication (jaw pain on chewing that resolves afterwards), neck stiffness, fever, and headaches in people with HIV, cancer or risk factors for thrombosis. ( Tramadol & Fioricet )
Pathophysiology
The brain itself is not sensitive to pain, because it lacks pain receptors. However, several areas of the head and neck do have nociceptors, and can thus sense pain. These include the extracranial arteries, large veins, cranial and spinal nerves, head and neck muscles and the meninges.
Headache often results from traction to or irritation of the meninges and blood vessels. The nociceptors may also be stimulated by other factors than head trauma or tumors and cause headaches. Some of these include stress, dilated blood vessels and muscular tension. Once stimulated, a nociceptor sends a message up the length of the nerve fiber to the nerve cells in the brain, signaling that a part of the body hurts.
It has been suggested that the level of endorphins in one's body may have a great impact on how people feel headaches. Thus, it is believed that people who suffer from chronic headaches or severe headaches have lower levels of endorphins compared to people who do not complain of headaches. ( Tramadol & Fioricet )
Diagnosis approach
The American College of Emergency Physicians have guidelines on the evaluation and management of adult patients who have a nontraumatic headache of acute onset.
While, statistically, headaches are most likely to be primary (non serious and self-limiting), some specific secondary headache syndromes may demand specific treatment or may be warning signals of more serious disorders.
Differentiating between primary and secondary headaches can be difficult.As it is often difficult for patients to recall the precise details regarding each headache, it is often useful for the sufferer to fill-out a "headache diary" detailing the characteristics of the headache.
Treatment
Chronic headaches
In recurrent unexplained headaches keeping a "headache diary" with entries on type of headache, associated symptoms, precipitating and aggravating factors may be helpful. This may reveal specific patterns, such as an association with medication, menstruation or absenteeism or with certain foods. It was reported in March 2007 by two separate teams of researchers that stimulating the brain with implanted electrodes appears to help ease the pain of cluster headaches.
Acupuncture has been found to be beneficial in chronic headaches of both tension type and migraine type. Research comparing acupuncture to 'sham' acupuncture has shown that the results of acupuncture may be due to the placebo effect. ( Tramadol & Fioricet )
One type of treatment, however, is usually not sufficient for chronic sufferers and they may have to find a variety of different ways of managing, living with, and seeking treatment of chronic daily headache pains.Epidemiology
During a given year, 90% of people suffer from headaches. Of the ones seen in the ER, about 1% have a serious underlying problem.
Primary headaches account for more than 90% of all headache complaints, and of these, episodic tension-type headache is the most common.
It is estimated that women are three times more prone than men to suffer from migraines. Also, the prevalence of this particular type of headache seems to vary depending on the specific area of the world where one lives. However, migraines appear to be experienced by 12% to 18% of the population.History
The first recorded classification system that resembles the modern ones was published by Thomas Willis, in De Cephalalgia in 1672. In 1787 Christian Baur generally divided headaches into idiopathic (primary headaches) and symptomatic (secondary ones), and defined 84 categories.