Headache is the common symptom of an ache or pain affecting the head or neck, with many possible causes including fever, emotional tension (with spasm of neck muscles), or nasal sinus infection. Very occasionally, headache is a symptom of a serious underlying disorder.
The pain of a headache does not come from the brain, which has no sensory nerves, but arises from the meninges (the membranes around the brain) and from the scalp and its blood vessels and muscles. The pain is produced by tension in, or stretching of these structures.
The pain may be felt all over the head or may occur in only one part – for example, in the forehead, in the back of the neck, or one side of the head. Sometimes the pain moves to another part of the head during the course of the headache. The pain of headache may be superficial or deep, throbbing or sharp, and there may also be accompanying or preliminary symptoms, such as nausea, vomiting, and visual or sensory disturbances.
Types of headache
Many headaches are simply the body's response to some adverse stimulus, such as hunger or a change in the weather. These headaches usually clear up in a few hours and leave no after-effects.
Tension headaches caused by tightening in the muscles of the face, neck, and scalp as a result of stress or poor posture, are also common. They may last for days or weeks and can cause varying degrees of discomfort.
Some types of headache are especially painful and persistent but nevertheless are not an indication of a progressive underlying disorder. Migraine is a severe, incapacitating headache preceded or accompanied by zigzag or flashing visual sensations or tingling in part of the body, followed by an often one-sided severe-throbbing headache. This may be accompanied by nausea, vomiting, and sensitivity to light. There is often a family history. Cluster headaches cause intense pain behind one eye and may wake the sufferer nightly for periods of weeks or months.
Common causes of headache include hangover, irregular meals, prolonged travel, poor posture, a noisy or stuffy work environment, excitement, and excessive sleep. Certain foods, such as cheese, chocolate, and red wine, trigger migraine attacks in susceptible people. Food additives may also cause headache. Other causes include sinusitis, toothache, head injury, and cervical osteoarthritis.
Meningeal inflammation, as in meningitis and subarachnoid hemorrhage, may also cause severe headache. The headache of raised intracranial pressure is often worse on waking and on coughing and may be a symptom of brain tumor, abscess, or aneurysm.
If headaches persist, without obvious cause, and don't respond to self-help treatment, medical advice should be sought. The doctor will ask about the nature and site of the pain and at what intervals the headaches occur. A careful general physical and neurological examination will be performed. CT scanning or MRI (magnetic resonance imaging) may be carried out if a neurological cause for the headaches is suspected.
Prevention is more important than treatment; many of the known causes can easily be avoided, particularly if the sufferer knows what triggers the headaches. Once a headache has started (provided it is not a migraine or cluster headache), one or more of the following measures should ease the pain: relaxing in a hot bath; lying down; avoidance of aggravating factors (such as excessive noise or a stuffy room); stretching and massaging the muscles in the shoulders, neck, face, and scalp; and taking a mild analgesic (painkiller); and sleeping.