You’re just sitting at your desk, working on a difficult task, watching a movie, or reading a book, when suddenly it feels as if a belt or vice is being tightened around your head or neck. Or, periodic headaches attack with accompanying nausea and increased sensitivity to light or sound.
Sound familiar? If so, you’ve suffered one of the many types of headache that can occur on its own or as part of another disease or health condition.
Anyone can experience a headache. Nearly 2 out of 3 children will have a headache by age 15. More than 9 in 10 adults will experience a headache sometime in their life. Headaches are the most common form of pain and a major reason cited for days missed at work or school, as well as visits to the doctor. Without proper treatment, headaches can be severe, debilitating and interfere with daily activities.
Some types of headache run in families, fade over time just to reoccur and yes, it’s possible to be impacted by more than one type of headache at the same time. Headaches are defined as a pain that comes from the upper neck or head. Since the brain itself has no nerves that can cause the sensation of pain, it originates from the tissues and structures that surround the skull or the brain. These include – the thin layer of tissue (periosteum) that surrounds bones, muscles that encase the skull, sinuses, eyes, and ears, as well as thin tissues that cover the surface of the brain and spinal cord (meninges), arteries, veins, and nerves. Any or all can all become painful when inflamed or irritated and cause a headache. The pain may be a dull ache, sharp, throbbing, constant, intermittent, mild, or intense.
Headaches occur when pain-sensitive nerve endings called nociceptors react to headache triggers (such as stress, certain foods or odors, or medications) and send messages through the trigeminal nerve. Information about touch, pain, temperature, and vibration in the head and neck is sent to the brain by this trigeminal nerve, one of 12 pairs of cranial nerves that start at the base of the brain.
The trigeminal nerve has three branches that conduct sensations from the scalp, the blood vessels inside and outside of the skull, the lining around the brain (the meninges), and the face, mouth, neck, ears, eyes, and throat.
This information is then sent to the thalamus, the brain’s “relay station” for pain sensation from all over the body. The thalamus controls the body’s sensitivity to light and noise and sends messages to parts of the brain that manage awareness of pain and the emotional response to it. Other parts of the brain may also be part of the process, causing nausea, vomiting, diarrhea, trouble concentrating, and other neurological symptoms.
The International Classification of Headache Disorders, published by the International Headache Society, is used to classify more than 150 types of primary and secondary headache disorders. They are all classified under these three categories:
These occur independently and are not caused by another medical condition. Primary or benign headaches are not due to an organic underlying condition. However, these common headaches are legitimate biological disorders, not psychological conditions. Science is rapidly progressing to better understand the cause of primary headaches. It’s uncertain what sets the process of a primary headache in motion. A cascade of events that affect blood vessels and nerves inside and outside the head causes pain signals to be sent to the brain. Brain chemicals called neurotransmitters are involved in creating head pain, as are changes in nerve cell activity (called cortical spreading depression). Migraine, cluster, and tension-type headache are the more familiar types of primary headache.
About 12% of the U.S. population experience migraine headaches. They are characterized by throbbing and pulsating pain caused by the activation of nerve fibers that reside within the wall of brain blood vessels traveling within the meninges.
Migraines headaches are recurrent attacks of moderate to severe pain that often strike one side of the head. Untreated attacks can last from 4 to 72 hours. Other common symptoms are increased sensitivity to light, noise, and odors; and nausea and vomiting. Routine physical activity, movement, or even coughing or sneezing can worsen pain.
In typical cases, the pain is on one side of the head, often beginning around the eye and temple before spreading to the back of the head. The pain is frequently severe and is described as throbbing or pulsating. Nausea is common, and many migraine patients have a watering eye, a running nose, or congestion. If these symptoms are prominent, they may lead to a misdiagnosis of sinus headaches. One way to remember the features of migraine is to use the word POUND
P is for pulsating pain
O for one-day duration of severe untreated attacks
U for unilateral (one-sided) pain
N for nausea and vomiting
D for disabling intensity.
Migraines occur most frequently in the morning, especially upon waking. Some people have migraines at predictable times, such as before menstruation or on weekends following a stressful week of work. Many people feel exhausted or weak following a migraine but are usually symptom-free between attacks.
A number of different factors can increase the risk of having a migraine. These factors, which trigger the headache process, vary from person to person and may include sudden changes in weather or environment, too much or not enough sleep, strong odors or fumes, emotion, stress, overexertion, loud or sudden noises, motion sickness, low blood sugar, skipped meals, tobacco, depression, anxiety, head trauma, hangover, some medications, hormonal changes, and bright or flashing lights. Medication overuse or missed doses may also cause headaches. In some 50 percent of migraine sufferers, foods or ingredients can trigger headaches. These include aspartame, caffeine (or caffeine withdrawal), wine and other types of alcohol, chocolate, aged cheeses, monosodium glutamate, some fruits and nuts, fermented or pickled goods, yeast, and cured or processed meats. Keeping a diet journal will help identify food triggers.
This is the most common type of headache. As its name indicates, stress triggers pain by causing the muscles in the neck, face, scalp, and jaw to contract. Tension-type headaches may also be caused by jaw clenching, intense work, missed meals, depression, anxiety, or too little sleep. Sleep apnea may also cause tension-type headaches, especially in the morning. The pain is usually mild to moderate and feels as if constant pressure is being applied to the front of the face, to the head or neck and even ear pain. It also may feel as if a belt is being tightened around the head. Most often the pain is felt on both sides of the head. People who suffer tension-type headaches may also feel overly sensitive to light and sound. Typically, tension-type headaches usually disappear once the period of stress or related cause has ended.
Tension-type headaches affect women slightly more often than men. They usually begin in adolescence and reach peak activity in the 30s. They have not been linked to hormones and do not have a strong hereditary connection.
There are two forms of tension-type headache: episodic tension-type headaches occur between 10 and 15 days per month, with each attack lasting from 30 minutes to several days. Although the pain is not disabling, the severity of pain typically increases with the frequency of attacks. Chronic tension-type attacks usually occur more than 15 days per month over a 3-month period. The pain, which can be constant over a period of days or months, strikes both sides of the head and is more severe and disabling than episodic headache pain. Chronic tension headaches can cause sore scalps-even combing your hair can be painful. Most individuals will have had some form of episodic tension-type headache prior to onset of chronic tension-type headache.
Depression and anxiety can cause tension-type headaches. Headaches may appear in the early morning or evening, when conflicts in the office or at home are anticipated. Other causes include physical postures that strain head and neck muscles (such as holding your chin down while reading or holding a phone between your shoulder and ear), degenerative arthritis of the neck, and temporomandibular joint dysfunction (TMJ).
Cluster headaches are often short in duration and usually cause pain on one side of the head, behind the eyes. The pain is commonly on one side, and it may be described as throbbing or constant in nature. Cluster headaches will typically occur about one to two hours after a person goes to bed. While they may have some symptoms similar to migraines, they usually don’t cause nausea. They usually cause the eyes to tear up and produce nasal congestion or a runny nose. These headaches can last for extended periods of time, known as the cluster period. The cluster period can be as long as six weeks. Cluster headaches may occur every day and more than once a day. The cause is unknown; however, this type of headache is rare and generally affects men age 20 to 40.
These are symptoms of another health disorder that causes pain-sensitive nerve endings to be pressed on or pulled or pushed out of place. Secondary headaches are those that are due to an underlying structural or infectious problem in the head or neck. This is a very broad group of medical conditions ranging from dental issues, sinusitis, trauma, withdrawing from medications including narcotics and over the counter anti-inflammatories such as ibuprofen, dehydration, “hangovers”, or life-threatening conditions like bleeding in the brain or infections like meningitis.
Cranial neuralgias, facial pain, and other headaches
Neuralgia means nerve pain. Cranial neuralgia describes inflammation of one of the 12 cranial nerves coming from the brain that control the muscles and carry sensory signals (such as pain) to and from the head and neck. Perhaps the most commonly recognized example is trigeminal neuralgia, which affects cranial nerve V (the trigeminal nerve), the sensory nerve that supplies the face and can cause intense facial pain when irritated or inflamed.
Headaches plague most of us at one time or another. But when they are acute, severe, or chronic, seek medical attention. Read next weeks post on how they area diagnosed, treated and when to seek medical care.