Headache is a pain or discomfort felt in the head. It is not a disease but a symptom of some other problem in the body, thus there are many possible causes. When someone gets a headache, it usually is temporary, and only very rarely is it a sign of serious illness.
Up to 50 million people in the United States annually seek medical help for migraine and other severe headaches. Every 10 seconds, someone in the United States goes to the emergency room with a migraine or other type of headache. The lost work hours due to migraine and other headaches cost an estimated $13 billion every year in the United States. It has been estimated that more than $1 billion is spent each year for over-the-counter remedies to relieve headaches.
A large percentage of women's headaches are related to their menstrual cycle * . Chronic * headaches may accompany emotional disturbances such as depression. Many times, headaches are just one of a number of symptoms, such as fever or dizziness, which are brought on by various diseases or injuries. Migraine headaches frequently are accompanied by nausea and other symptoms that are characteristic of the disorder.
The pain of headache may be mild, extremely severe, or anywhere in between. It may involve the entire head, one side only, the forehead, or the base of the skull, or it may seem to move around. The pain may be sharp, a dull ache, or throbbing. A headache may last a few minutes or hours. It may recur from time to time, or it may become chronic, coming back many times over an extended period.
Many people believe that the brain itself is involved in headaches, but neither the brain nor the skull has nerves that register pain. The sources of head pain are the nerve endings in the blood vessels and muscles in and around the head. Pain may be felt when these tissues become stretched, inflamed, or damaged. Headaches can arise in blood vessels within the brain, as well as in the meninges (meh-NIN-jeez), which are the sensitive membranes that cover the brain.
Many types of infection with fever, such as influenza (flu), cause headache. Other causes include drinking too much alcohol, heavy smoking, withdrawal * from caffeine, or inhaling a noxious gas, such as carbon monoxide. Contrary to popular belief, high blood pressure rarely is a direct cause of headache.
Headache is one of the symptoms of concussion and sometimes becomes chronic following this injury.
Rarely, headaches may be caused by brain abscesses, brain tumors * , bleeding into the brain, and meningitis (an inflammation of the membranes covering the brain).
Physicians often classify headaches as those caused by disease or injury; tension headaches; and vascular * headaches. Vascular headaches include migraine and a type called cluster headaches. Tension and migraine headaches are very common.
Headaches that are associated with emotional stress or muscular tension are called tension headaches. The muscular tension may be in the neck, face, or scalp. It may be the result of poor posture or of constantly bending over one's work. These headaches are extremely common, and almost everyone has them at one time or another. A person may have one after working on the computer too long or bending over while doing homework.
Pressures from school, friends, or family may play a role. Adults may develop tension headaches because of stress at work. Tension headaches may be mild to moderate and occur in various parts of the head. The feeling has been described as a steady ache or as a tight sensation.
The pain of tension headaches can be chronic or recurrent, sometimes coming on every day. Muscles near the site of the pain, such as at the back of the neck or on the sides of the head, are often tense and tender. Sometimes chronic tension headache is a symptom of depression.
Chronic Conditions Team. “When It Feels Like a Headache—But Isn't.” Health Essentials, September 3, 2015. http://health.clevelandclinic.org/2015/09/when-it-feels-like-a-migraine-but-isnt (accessed September 21, 2015).
Hochwald, Lambeth. “What Type of Headache Do I Have?” Mother Nature Network, September 16, 2015. http://www.mnn.com/health/fitness-well-being/stories/what-type-headache-do-I-have (accessed September 21, 2015).
“Migraine Severity Linked to Cholesterol Levels.” Renal and Urology News, September 17, 2015. http://www.renalandurologynews.com/cardiovascular-disease-cvd/migraine-severity-linked-to-cholesterol-levels/article/438058 (accessed September 21, 2015).
Morrone, Lisa. Overcoming Headaches and Migraines. Eugene, OR: Harvest House, 2008.
Ruoff, Gary. Knock Out Headaches. Ann Arbor, MI: Spry, 2013.
ACHE. “Tension-Type Headaches—The Basics.” American Headache Society. http://www.achenet.org/resources/tensiontype_headaches__the_basics (accessed June 7, 2016).
American Chiropractic Association (ACA). “Headaches & Chiropractic.” https://www.acatoday.org/content_css.cfm?CID=2186 (accessed July 16, 2015).
American Academy of Family Physicians. PO Box 11210, Shawnee Mission, KS 66207-1210. Toll-free: 800-274-2237. Website: http://www.aafp.org (accessed July 16, 2015).
American Academy of Neurology. 201 Chicago Ave., Minneapolis, MN 55415. Toll-free: 800-879-1960. Website: http://www.aan.com (accessed July 16, 2015).
American Headache Society. 19 Mantua Rd., Mt. Royal, NJ 08061. Telephone: 856-423-0043. Website: https://americanheadachesociety.org/ (accessed June 7, 2016).
National Headache Foundation. 820 N. Orleans, Suite 411, Chicago, IL 60610. Toll-free: 888-643-5552. Website: http://www.headaches.org (accessed July 16, 2015).
* blood clot is a thickening of the blood into a jellylike substance that helps stop bleeding. Clotting of the blood within a blood vessel can lead to blockage of blood flow.
* menstrual cycle (MENstroo- al SY-kul) culminates in menstruation (men-stroo-AYshun), the discharging through the vagina of blood, secretions, and tissue debris from the uterus that recurs at approximately monthly intervals in females of reproductive age.
* chronic (KRAH-nik) means lasting a long time or recurring frequently.
* glaucoma is a group of disorders that cause pressure to build in the eye, which may result in vision loss.
* glaucoma is a group of disorders that cause pressure to build in the eye, which may result in vision loss.
* withdrawal is a group of symptoms that occurs when a drug that causes physical or psychological dependence is regularly used for a long time and then suddenly discontinued or significantly decreased in dosage.
* tumors (TOO-morz) are abnormal growths of body tissue that have no known cause or physiologic purpose. Tumors may or may not be cancerous.
* vascular refers to veins and arteries (the blood vessels).