The Facts about Headaches

Nearly everyone has suffered the pain of a headache. In fact, according to the American Council for Headache Education, nearly 90% of men and 95% of women have had at least one headache during the past year.

But what actually hurts when you have a headache? The bones of the skull and tissues of the brain itself never hurt, because they lack pain-sensitive nerve fibers. Several areas of the head can hurt, including a network of nerves which extends over the scalp and certain nerves in the face, mouth, and throat. Also sensitive to pain, because they contain delicate nerve fibers, are the muscles of the head and blood vessels found along the surface and at the base of the brain.

Diagnosis
A physician's detailed question-and-answer session with a patient can often produce enough information for a diagnosis. Many types of headaches have clear-cut symptoms which fall into an easily recognizable pattern. Most physicians will also obtain a full medical history from the patient, inquiring about past head trauma or surgery, eye strain, sinus problems, dental problems, difficulties with opening and closing of the jaw, and the use of medications.

A complete and careful physical and neurological examination will exclude many possibilities and the suspicion of aneurysm, meningitis, or certain brain tumors. A blood test may be ordered to screen for thyroid disease, anemia, or infections which might cause a headache. In more complex cases, a physician might also order an electroencephalogram (EEG), a computed tomographic (CT) scan and/or a magnetic resonance imaging (MRI) scan.

The physician analyzes the results of all these diagnostic tests along with a patient's medical history and examination in order to arrive at a diagnosis. Headaches are diagnosed as:

• Muscle contraction (tension)
• Vascular
• Traction
• Inflammatory

Muscle contraction headaches appear to involve the tightening or tensing of facial and neck muscles.

The most common type of vascular headache is migraine. After migraine, the most common type of vascular headache is the toxic headache produced by fever. Other kinds of vascular headaches include "cluster" headaches, which cause repeated episodes of intense pain, and headaches resulting from high blood pressure.

Traction and inflammatory headaches are symptoms of other disorders, ranging from stroke to sinus infection. Like other types of pain, headaches can serve as warning signals of more serious disorders. This is particularly true for headaches caused by inflammation, including those related to meningitis as well as those resulting from diseases of the sinuses, spine, neck, ears, and teeth.

Muscle Contraction Headaches
Tension headache is named not only for the role of stress in triggering the pain, but also for the contraction of neck, face, and scalp muscles brought on by stressful events. Tension headache is a severe but temporary headache with mild to moderate pain that feels like pressure is being applied to the head or neck. The headache usually disappears after the stress is over.

Ninety percent of all headaches are classified as tension/muscle contraction headaches. People who suffer infrequent muscle-contraction headaches may benefit from a hot shower or moist heat applied to the back of the neck. Physical therapy, massage, and gentle exercise of the neck may also be helpful.

By contrast, chronic muscle-contraction headaches can last for weeks, months, and sometimes years. The pain of these headaches is often described as a tight band around the head or a feeling that the head and neck are in a cast. The pain is steady, and is usually felt on both sides of the head. Chronic muscle contraction headaches can cause sore scalps - even combing one's hair can be painful.

Occasionally, muscle contraction headaches will be accompanied by nausea, vomiting, and blurred vision, but there is no pre-headache syndrome as with migraine. Muscle-contraction headaches have not been linked to hormones or foods, nor is there a strong hereditary connection.

Research has shown that for many people, chronic muscle-contraction headaches are caused by depression and anxiety. These people tend to get their headaches in the early morning or evening when conflicts in the office or home are anticipated.

Certain physical postures that tense head and neck muscles - such as holding one's chin down while reading - can lead to head and neck pain. So can prolonged writing under poor light, or holding a phone between the shoulder and ear, or even gum-chewing.

More serious problems that can cause muscle-contraction headaches include degenerative arthritis of the neck and temporomandibular joint dysfunction, or TMD. TMD is a disorder of the joint between the temporal bone (above the ear) and the mandible or lower jaw bone. The disorder results from poor bite and jaw clenching.

Treatment: Treatment for muscle-contraction headache varies. The first consideration is to treat any specific disorder or disease that might be causing the headache. For example, arthritis of the neck is treated with anti-inflammatory medication and TMD may be helped by corrective devices for the mouth and jaw.

Acute tension headaches not associated with a disease are treated with analgesics like aspirin and acetaminophen. Stronger analgesics are sometimes prescribed, but since prolonged use of these drugs can lead to dependence, patients taking them should have periodic medical checkups and follow their physicians' instructions carefully.

Non-drug therapy for chronic muscle-contraction headaches includes biofeedback, relaxation training, and counseling. People with chronic muscle-contraction headaches my also be helped by taking antidepressants or MAO inhibitors.

Vascular Headaches: Classic and Common Migraine
Migraine headaches are usually characterized by severe pain on one or both sides of the head, an upset stomach, and at times disturbed vision. Sensitivity to light is a standard symptom of the two most prevalent types of migraine-caused headache: classic and common.

Classic Migraine: The major difference between the two types is the appearance of neurological symptoms 10 to 30 minutes before a classic migraine attack. These symptoms are called an aura. The person may see flashing lights or zigzag lines, or may temporarily lose vision. Other classic symptoms include speech difficulty, weakness of an arm or leg, tingling of the face or hands, and confusion.

The pain of a classic migraine headache may be described as intense, throbbing, or pounding and is felt in the forehead, temple, ear, jaw, or around the eye. Classic migraine starts on one side of the head but may eventually spread to the other side. An attack lasts 1 to 2 pain-wracked days.

Common Migraine: Common migraine - a term that reflects the disorder's greater occurrence in the general population - is not preceded by an aura. But some people experience a variety of vague symptoms beforehand, including mental fuzziness, mood changes, fatigue, and unusual retention of fluids. During the headache phase of a common migraine, a person may have diarrhea and increased urination, as well as nausea and vomiting. Common migraine pain can last 3 or 4 days.

Although the precise cause of migraine headaches is not known, there seems to be general agreement that a key element is blood flow changes in the brain: people who get migraine headaches appear to have blood vessels that overreact to various triggers.

Migraines are more common in adult women. Both sexes may develop migraine in infancy, but most often the disorder begins between the ages of 5 and 35. The relationship between female hormones and migraine is still unclear.

Migraine Triggers: Although many sufferers have a family history of migraine, its hereditary nature is still unknown. Fatigue, glaring or flickering lights, changes in the weather, and certain foods can set off migraine. While a food-triggered migraine usually occurs soon after eating, other triggers may not cause immediate pain. For example, migraines that wake people up in the middle of the night are believed to result from a delayed reaction to stress.

Migraine Treatment: Drug therapy, biofeedback training, stress reduction, and elimination of certain foods from the diet are the most common methods of preventing and controlling migraine and other vascular headaches. Regular exercise can also reduce the frequency and severity of migraine headaches.

During a migraine headache, temporary relief can sometimes be obtained by applying cold packs to the head or by pressing on the bulging artery found in front of the ear on the painful side of the head.

Other Types of Vascular Headaches
After migraine, the most common type of vascular headache is the toxic headache produced by fever. Pneumonia, measles, mumps, and tonsillitis are among the diseases that can cause severe toxic vascular headaches. Toxic headaches can also result from the presence of foreign chemicals in the body. Other kinds of vascular headaches include "clusters," which cause repeated episodes of intense pain, and headaches resulting from a rise in blood pressure.

Chemical. Repeated exposure to nitrite compounds can result in a dull, pounding headache that may be accompanied by a flushed face. Nitrite, which dilates blood vessels, is found heart medicine, but is also used as a chemical to preserve hot dogs and other processed meats.

Eating foods prepared with monosodium glutamate (MSG) can also result in headache. Soy sauce, meat tenderizer, and a variety of packaged foods contain this chemical, said to be a flavor enhancer.

Headache can result from exposure to poisons, even common household varieties like insecticides, carbon tetrachloride, and lead. Children who ingest flakes of lead paint may develop headaches. So may anyone who has contact with lead batteries or lead-glazed pottery. Artists and industrial workers may experience headaches after exposure to materials that contain solvents like benzene, found in turpentine, spray adhesives, rubber cement, and inks.

Drugs such as amphetamines can cause headaches. Another type of drug-related headache occurs during withdrawal from long-term therapy with the anti-migraine drug ergotamine tartrate.

There are several suggested treatments for the pain of alcohol hangovers; in addition the hangover headache might be reduced by taking honey, which speeds alcohol metabolism, or caffeine, a constrictor of dilated arteries. Caffeine, however, can cause headaches as well as cure them. Heavy coffee drinkers often get headaches when they try to break the caffeine habit.

Cluster. Cluster headaches, named for their repeated occurrence over weeks or months at roughly the same time of day or night in clusters, begin as a minor pain around one eye, eventually spreading to that side of the face. The pain quickly intensifies, compelling the victim to pace the floor or rock in a chair. Other symptoms include a stuffed and runny nose and a droopy eyelid over a red and tearing eye.

Cluster headaches last between 30 and 45 minutes. Many people have cluster bouts during the spring and fall. Unlike migraine, cluster headaches are more common in men and do not run in families.

Studies of cluster patients show that they are likely to have hazel eyes and that they tend to be heavy smokers and drinkers. The exact connection between these substances and cluster attacks is not known.

Specific anti-migraine drugs can prevent or subdue a cluster. Another option that works for some cluster patients is rapid inhalation of pure oxygen through a mask for 5 to 15 minutes. The oxygen seems to ease the pain of cluster headache by reducing blood flow to the brain.

In chronic cases of cluster headache, certain facial nerves may be surgically cut or destroyed to provide relief. These procedures have had limited success.

Pressure. Chronic high blood pressure can cause headache, as can rapid rises in blood pressure like those experienced during anger, vigorous exercise, or sexual excitement. The severe "orgasmic headache" occurs right before orgasm and is believed to be a vascular headache. Since sudden rupture of a cerebral blood vessel can occur, this type of headache should be evaluated by a doctor.

Traction and Inflammation Headaches
Like other types of pain, sometimes headaches can serve as warning signals of more serious disorders. This is particularly true for headaches caused by traction or inflammation.

Traction headaches can occur if the pain-sensitive parts of the head are pulled, stretched, or displaced, as, for example, when eye muscles are tensed to compensate for eyestrain. Headaches caused by inflammation include those related to meningitis as well as those resulting from diseases of the sinuses, spine, neck, ears, and teeth. Ear and tooth infections and glaucoma can cause headaches. In oral and dental disorders, headache is experienced as pain in the entire head, including the face. These headaches are treated by curing the underlying problem. This may involve surgery, antibiotics, or other drugs.

Characteristics of the various types of more serious traction and inflammatory headaches vary by disorder:

• Brain tumor. Brain tumors are diagnosed in about 11,000 people every year. As they grow, these tumors sometimes cause headache by pushing on the outer layer of nerve tissue that covers the brain or by pressing against pain-sensitive blood vessel walls.
• Stroke. Headache may accompany several conditions that can lead to stroke, including hypertension or high blood pressure, arteriosclerosis, and heart disease. Headaches are also associated with completed stroke, when brain cells die from lack of sufficient oxygen.
  Headaches are also associated with transient ischemic attacks (TIAs), sometimes called "mini-strokes," which result from a temporary lack of blood supply to the brain. The head pain occurs near the clot or lesion that blocks blood flow. The similarity between migraine and symptoms of TIA can cause problems in diagnosis. The rare person under age 40 who suffers a TIA may be misdiagnosed as having migraine; similarly, TIA-prone older patients who suffer migraine may be misdiagnosed as having stroke-related headaches.
• Spinal tap. About one-fourth of the people who undergo a lumbar puncture (spinal tap) develop a headache. Since headache pain occurs only when the patient stands up, the "cure" is to remain lying down until the headache runs its course - anywhere from a few hours to several days.
• Head trauma. Headaches may develop after a blow to the head, either immediately or months later. Occasionally the cause is ruptured blood vessels which result in an accumulation of blood called a hematoma. This mass of blood can displace brain tissue and cause headaches as well as weakness, confusion, memory loss, and seizures. Hematomas can be drained to produce rapid relief of symptoms.
• Temporal arteritis. Arteritis, an inflammation of certain arteries in the head, primarily affects people over age 50. Symptoms include throbbing headache, fever, and loss of appetite. Some patients experience blurring or loss of vision. Prompt treatment with corticosteroid drugs helps to relieve symptoms.
• Meningitis and encephalitis headaches are caused by infections of meninges - the brain's outer covering - and in encephalitis, inflammation of the brain itself.
• Trigeminal neuralgia. Trigeminal neuralgia, or tic douloureux, results from a disorder of the trigeminal nerve, which runs throughout the face, teeth, mouth, and nasal cavity. Symptoms are headache and intense facial pain that comes in short, excruciating jabs set off by the slightest touch to or movement of trigger points in the face or mouth. Many cases of trigeminal neuralgia are controlled with drugs. Patients who do not respond to drugs may be helped by surgery on the trigeminal nerve.
• Sinus infection. In a condition called acute sinusitis, a viral or bacterial infection of the upper respiratory tract spreads to the membrane that lines the sinus cavities. When one or more of these cavities are filled with fluid from the inflammation, they become painful. Treatment of acute sinusitis includes antibiotics, analgesics, and decongestants.

When You Should See a Physician
Not all headaches require medical attention. Some result from missed meals or occasional muscle tension and are easily remedied. But some types of headache are signals of more serious disorders, and call for prompt medical care. These include:

• Sudden, severe headache
• Sudden, severe headache associated with a stiff neck
• Headache associated with fever
• Headache associated with convulsions
• Headache accompanied by confusion or loss of consciousness
• Headache following a blow on the head
• Headache associated with pain in the eye or ear
• Persistent headache in a person who was previously headache free
• Recurring headache in children
• Headache that interfere with normal life

Research
The National Institute of Neurological Disorders and Stroke (NINDS) conducts research relating to headaches at its laboratories at the National Institutes of Health (NIH), and supports additional research through grants to major medical institutions across the country. NINDS also supports and conducts studies to improve the diagnosis of headaches and to find ways to prevent them.

Today's headache research offers hope. The work of NINDS-supported scientists around the world promises to improve our understanding of this complex disorder and provide better tools to treat it.

The information in this article has been made available by the National Institute of Neurological Disorders and Stroke. More details are available on the Headache Information Page and in Headache: Hope through Research.

Each year, Medical College of Wisconsin physicians care for more than 180,000 patients, representing nearly 500,000 patient visits. Medical College physicians practice at Children's Hospital of Wisconsin, Froedtert Memorial Lutheran Hospital, the Milwaukee VA Medical Center, and many other hospitals and clinics in Milwaukee and southeastern Wisconsin.