What causes Headaches?
Headache was one of the first symptoms recorded by man, and today it is the most common of all medical complaints. More than 70% of people get headaches, ranging from an occasional aggravation to chronic, crushing head pain. Headaches cost society a large fortune each year in lost productivity.
There are many structures in the head which may become inflamed, compressed or irritated, leading to headache pain. These include nerves, blood vessels and muscles of the face, scalp and neck, teeth, the lining of the brain, sinuses, joints and other soft tissues. A number of chemicals released by arteries and nerves may set up “vicious cycles” in these structures or tissues causing a headache to become long lasting or continuous.
Investigating a Headache
Many types of headaches have a recognizable pattern. For this reason, a detailed clinical history is essential in making a diagnosis. Occasionally, additional tests may be necessary. Blood tests may screen for thyroid disease, anaemia, or infections. X-rays may be taken to rule out bony abnormalities or sinus infection. Occasionally patients with unusual headaches may require a computed tomographic (CT) scan or magnetic resonance imaging (MRI) which demonstrate internal brain structures or biochemistry of the brain. An eye examination may be done to check for weakness in the eye muscle or poor eyesight. In certain cases an angiogram may be undertaken to reveal any abnormalities in the blood vessels in the brain. If meningitis is suspected, a Lumbar Puncture may be performed.
Types of Headache
Headaches without underlying disease are termed “primary”, and include tension, migraine and cluster headaches. About 95% of all headaches are primary. Less than 5% of headaches signal a serious medical condition.
90% of primary headaches are tension-type, affecting men and women about equally. They are usually diffuse with pain over the top of the head or back of the neck. It may feel like fullness or pressure, as if a constricting band is surrounding your head. Neck and shoulder muscles may be tense. The pain may go away after an hour, may last several days, or may become chronic. The headache pain waxes and wanes. They are most often caused by anxiety or stress and occur more commonly in people with poor posture, those who strain their neck and shoulders a lot and people who work at stationary, repetitive tasks.
These are relatively uncommon, but very severe, affecting men far more often than women. Sufferers are typically heavy smokers. They have an abrupt onset and can occur at any time, but they most commonly occur 2 to 3 hours after you fall asleep. They are characterized by intense burning, boring pain frequently located in or around one eye and temple or in a cheek or jaw. The affected eye may be bloodshot and teary. The nostril on that side may be blocked or run profusely. Other features may be reduced pupil size on the painful side, a drooping eyelid, a flushed face and a sweaty brow. The pain intensifies within 5 – 10 minutes to a peak that persists for up to 2 hours. They can occur daily for days, weeks, or months, before a remission period.
About 6% of primary headaches are migraine. It has a strong genetic component, and is about 3 times more common in women than men. Most often the disorder begins between the ages of 5 and 35 years old.
Migraine headaches are characterized by intense, throbbing head pain, worsened by physical activity. It is felt in the forehead, temple, ear, jaw, or around the eye. Most migraines are one-sided. They are long lasting (from 4 to about 72 hours), and often associated with nausea, vomiting, and sensitivity to light and/or sound. Aura. About 10-20% of migraine patients have auras. These are neurological symptoms that usually precede the headache and include visual disturbances, tingling, numbness or weakness on one side of the face or body, speech problems or confusion.
What causes Migraine?
Migraine sufferers appear to have blood vessels that over react to various triggers. These cause spasm and constriction of the nerve-rich arteries in the brain followed by dilation of certain arteries within the brain, neck and scalp. Pain-producing substances called prostaglandins and a chemical called serotonin are involved. The release of these chemicals and the dilation of arteries stimulate pain receptors in the head, resulting in a throbbing headache pain.
These activate an already existing imbalance of chemicals in the brain. Common triggers include hormone changes, diet (alcohol, especially red wine or beer; aged cheeses; chocolate; pickled foods; monosodium glutamate; aspartame and caffeine), stress, weather changes, season, altitude, time zone, sleep patterns or meal times. Bright lights, unusual odours, medications or polluted air may also trigger migraines.
OTHER CAUSES OF HEADACHE
Some headaches, called “secondary” headaches, result from a medical condition. These conditions include sinus infections, abnormalities of the Temporomandibular joint (TMJ) connecting the jaw to the skull, brain tumours, middle ear infection, head trauma, eyestrain or eye infections, arteritis (inflammation of arteries), meningitis (inflammation of the brain’s outer covering) and head or neck neuralgia (inflammation of nerves).
Treatment of Headache & Migraine
Rest, heat or ice packs alone may relieve an occasional headache. If not, try an over-the-counter pain reliever. Take the minimal dose needed to relieve pain. Overuse may cause chronic daily headaches (“rebound” headaches). If these measures fail to control the headache, other medication may be necessary. Migraine medications fall into two broad categories: abortive drugs to stop or reduce pain after a headache starts and prophylactic drugs to prevent headaches. Abortive medications include “Serotonin agonists,” which work by influencing the behaviour of serotonin; vasoconstrictors, which prevent blood vessel swelling; anaesthetic nasal drops; anaelgesics and Non Steroidal Anti-Inflammatories. Prophylactic medications include antidepressants, Serotonin antagonists, Beta-blockers, calcium channel blockers and anti-seizure drugs. Inhalation of 100% oxygen has been shown to be effective for cluster headaches.
Over the long-term, combat headaches by controlling triggers, careful use of pain relievers to avoid “rebound” headaches, stopping smoking and avoiding alcohol during a headache, (especially cluster headaches). Manage stress and exercise regularly. Treatments such as physiotherapy or biofeedback may be effective.
Headaches may signal a serious medical condition. Contact your doctor if your headache:
- is accompanied by confusion, unconsciousness or convulsions
- involves pain in the eye or ear
- is accompanied by fever or nausea
- occurs after a blow to the head
- is persistent in someone previously free of headaches
- is recurrent, especially in children
- interferes with normal life.
Dealing with headache takes determination combined with a well-rounded approach. It means balancing use of medications with exercise, regular and nutritious meals, and adequate rest. Your goal is to attack headache pain from all sides. Together with advances in understanding headache, the reward is that you control your pain so that the pain doesn’t control you.