Most people have headaches from time to time. Some seem to get more than their share! But one person’s headache is not necessarily the same as another’s, for headaches manifest in many different ways.

Some people feel pain in only one part of the head or behind the eyes, whereas some experience a whole-head pounding sensation. Some people experience nausea, while others do not. The pain may seem dull or sharp. It may be short or very, very long in duration, lasting anywhere from a few minutes to a few days. Fortunately, very few headaches have serious underlying causes, but those that do require urgent medical attention.

What Causes Headaches?

Some causes of headaches are:

  • Drug reactions
  • Temporomandibular joint dysfunction (TMJ)
  • Tightness in the neck muscles
  • Low blood sugar
  • High blood pressure
  • Stress
  • Fatigue

Recurrent Headaches

There are three types of headaches that generally return again and again:

  1. Tension headaches (also called cervicogenic headaches)
  2. Migraine headaches
  3. Cluster headaches
Fingers demonstrating tension

A tension headache may be described as a feeling of a tight band or dull ache around the head or behind the eyes. A frequent cause is a subluxation in the upper back or neck.

Tension Headaches

The most common recurring headaches are of the tension type, and these affect at least 75% of all headache sufferers. This type of headache is often described as a constant dull, achy feeling, affecting one or both sides of the head, or as a tight band or dull ache around the head or behind the eyes.

Tension headaches (sometimes called stress headaches) may result from stress or bad posture that stresses the spine and muscles in the upper back and neck. People who hold desk jobs will tend to have headaches for this reason.

Tension headaches usually begin in the middle or towards the end of the day, not in the morning, with the pain beginning gradually. They may last for just minutes or for days at a time. (In the worst cases, these headaches can go on for months.) Although the pain can sometimes be severe, tension headaches are not usually associated with other symptoms, such as a throbbing sensation, nausea, or vomiting.

The most common cause of tension headaches is a muscle spasm resulting from a subluxation in the upper back or the neck (especially the upper neck), usually in association with active trigger points. The way this happens is as follows:

  1. Due to the subluxation, the top cervical vertebrae lose their normal motion or position
  2. A small muscle called the rectus capitis posterior minor (RCPM) muscle goes into spasm.
  3. This small muscle has a tendon that slips between the upper neck and the base of the skull and attaches to a thin tissue (called the dura mater) that covers the brain.  So, when the RCPM muscle goes into spasm, it tugs the dura mater, which is very pain-sensitive, and this causes the headache.

Another cause of tension headaches, especially in people who have had a whiplash injury, is the referred pain from trigger points in the Sternocleidomastoid (SCM) or levator muscle, found on the side of the neck.

Lightning illustrates the pain of migraine

Many of those who suffer from migraines experience visual symptoms called an “aura” just prior to an attack that is often described as seeing flashing lights.

Migraine Headaches

About 25 million people in the U.S. experience migraine headaches annually, and about 75% of these are women. Some have attacks several times a month; others, less than once per year. Fortunately, most people report that migraines occur less frequently and become less and less severe with age.

A migraine is an intense, throbbing headache often associated with nausea as well as an over sensitivity to light or noise. It can last for just a few hours or for several days. Just prior to an attack, many migraine sufferers experience a visual symptom called an “aura,” which they might describe as flashing lights, halos, zigzag lines, or even a temporary loss of vision. The aura may also create tingling or numbness on one side of the body.

The anatomical cause of a migraine headache seems to be a constriction of blood vessels in the brain, followed by a dilation of blood vessels.

  1. First, constriction causes a decrease in blood flow, which is what leads to the visual symptoms that many people experience as an “aura.” Even people who don’t see the classic migraine aura can usually tell an attack is imminent, due to other symptoms they usually experience before a migraine.
  2. Second, dilation of blood vessels allows a rapid increase in blood flow to the head, leading to the pounding headache. With each heart beat, another shock wave is being sent through the carotid arteries in the neck up into the brain.

There are only conflicting theories about why the blood vessels constrict in the first place. What is known is that some things can trigger migraines, such as lack of sleep, stress, flickering lights, strong odors, changing weather patterns, and foods that are high in the amino acid, tyramine. Knowing this, a person can reduce the likelihood of migraine headaches by making some lifestyle changes.

Fireworks depict a cluster headache

Cluster headaches are short in duration and usually felt on one side of the head behind the eyes. They come in clusters, several during one day.

Cluster Headaches

Cluster headaches affect a million people annually in the United States and, unlike migraines, they are much more common in men. This is the only type of headache that tends to occur at night.

This type of headache is excruciating, but very short-lived, usually felt behind an eye on one side of the head, and probably related to dilation of the blood vessels in the brain (like migraines).

The name comes from the pattern of occurrence – one to four times per day, over a period of several days.  After one cluster of headaches is over, it may be months or even years before a replay.

Chiropractic Care for Headaches

The best results from chiropractic adjustments have been for tension headaches, especially those originating in the neck.

Researchers at the Duke University Evidence-Based Practice Center in Durham, NC, published a report in 2001 stating that “spinal manipulation resulted in almost immediate improvement for those headaches that originate in the neck and had significantly fewer side effects and longer-lasting relief of tension-type headache than commonly prescribed medications.” An earlier study published in the Journal of Manipulative and Physiological Therapeutics found that spinal manipulative therapy was very effective for treating tension headaches, and that even people who stopped chiropractic treatment after four weeks enjoyed sustained benefits, in contrast to patients receiving pain medication.

Of course, each case is different and requires a thorough evaluation to determine a proper course of chiropractic care. In most cases of tension headaches, however, significant improvement is accomplished through manipulation of the upper two cervical vertebrae, coupled with adjustments to the junction between the cervical and thoracic spine. This is also effective in most cases of migraine headaches, given that the patient avoids food and lifestyle triggers.

Headache Trigger Points

Trigger point therapy for headaches usually addresses these muscles:

Splenius Muscles

The splenius muscles are comprised of two separate muscles, both of which start at the upper back. The splenius capitis terminates at the base of the skull and the splenius cervicis ends at the upper cervical vertebrae. Trigger points in the splenius muscles are a typical cause of headache pain that travels through the head to the back of the eye or the top of the head.


The suboccipitals are a group of four small muscles that are responsible for proper movement and positioning between the first cervical vertebra and the base of the skull. Trigger points in these muscles will cause pain that seems to be coming from inside the head, extending from the back of the head to the eye and forehead. This may feel like the whole side of the head hurts in a pain pattern similar to that of a migraine.

Sternocleidomastoid (SCM)

The sternocleidomastoid (SCM) muscle runs from the base of the skull – behind the ear – down the side of the neck to attach in front to the top of the sternum (breastbone). The potential effects of SCM trigger points include balance problems, dizziness, nausea, visual disturbances, and referred pain (such as deep eye pain, headaches over the eye, and even earaches).

Trapezius Muscle

The trapezius muscle is the very large, flat muscle in the upper and mid back. One trigger point located at the very top refers pain to the temple and back of the head, sometimes causing headaches. This trigger point is capable of producing satellite trigger points in temple or jaw muscles, and this can lead to pain in the jaw or teeth.

Avoid Headache Triggers

  • In addition to stress, a menstrual period or certain foods, odors, or changes in weather are among the many factors that may also trigger headaches.
  • Emotional triggers such as depression, anxiety, frustration, letdown, or even pleasant excitement may bring on a headache.
  • Keeping a headache diary will help you determine whether factors such as food or changes in the weather or your mood have any relationship to the pattern of your headaches.
  • Repeated exposure to nitrite compounds can result in a dull, pounding headache, sometimes accompanied by a flushed face. Nitrite dilates blood vessels and is found in such diverse substances as heart medicine and dynamite. The main source of nitrite to avoid is the chemical used to preserve meat. Hot dogs and other processed meats containing sodium nitrite can cause headaches.
  • Eating foods prepared with monosodium glutamate (MSG) can result in headache. This chemical, marketed as a flavor enhancer, is an ingredient in some soy sauces, meat tenderizers, various packaged foods, and some restaurant meals.
  • Headache can also result from exposure to poisons, even common household varieties like carbon tetrachloride, insecticides, and lead. For example, children who ingest flakes of lead paint may develop headaches, and so may anyone who has contact with lead batteries or lead-glazed pottery.
  • Foods that are high in the amino acid tyramine should also be avoided. Examples are ripened cheeses (cheddar, brie, etc.), chocolate, pickled or fermented foods, smoked fish, cured meats, some types of beer, and protein foods that have been stored for a long time or not been kept cold enough.