What is a headache?
The term headache refers to pain in the head and neck region. In true sense usually headache is a symptom of an underlying cause rather than a disease itself (secondary headache) but sometimes headache arise from chemical abnormality in brain (primary headache). The structures adjacent to brain tissue namely blood vessels, nerves, muscles, periosteum (outer surface) of the skull bones are pain sensitive but not the brain tissue itself since it lacks the pain carrying nerves. Headaches are typically more common among females than males.
Symptoms of headache vary according to the type.
- Headache can be localized or generalized, sudden onset (acute) or can build up gradually.
- The pain can be sharp, dull, throbbing in nature.
- It can be associated with nausea, vomiting, redness of the eye or a running nose.
- Some particular types of headache may be precipitated by stress, sun exposure, trauma, change in sleep pattern, alcohol intake and an empty stomach (skipping meals).
Head ache can occur due to various reasons broadly classified as primary or secondary. Primary headaches are not associated with any underlying disease but rather with manifestation of some underlying chemical imbalance in the structures adjacent to the brain. Secondary causes of headaches, where the pain in the occurs as a symptom of an underlying medical condition includes :
- Brain aneurysm (bulging of arteries)
- Brain arteriovenous malformation (AVM,structural abnormality)
- Brain tumor
- Head trauma
- Meningitis and encephalitis
- Alcohol hangover
- Stroke (due to rupture of blood vessel)
Risk factors depends upon the type of the headache but broadly include
- Environmental changes (bright light, excessive heat, cold)
- Tight fitting headwear
- Excessive use of pain killers or intake of glyceryl trinitrate (anti-angina drug)
- Structural defect of brain (Chiari malformation)
- Alcohol intake (hangover)
- Hormonal changes
Types of Headaches
There are four conditions known to cause primary headache include cluster headaches, migraines, tensions headaches and trigeminal cephalgia.
It is characterized by severe excruciating one sided pain with redness and drooping of the eye, running or stuffy nose, increased sweating paleness of the face (one-sided) and restlessness. Patients do not prefer lying down as it may increase the intensity of the pain. Although the exact cause is not known cluster headache usually occurs due to sudden release of the brain chemical serotonin.
Migraines are a clinical condition characterized by throbbing, pounding usually one sided headache and commonly preceded by aura (warning signal) like blurring of vision, eye pain, seeing floating objects and so on. It is commonly believed that migraine occurs due to release of chemicals in the brain and nerve stimulation which ultimately reduces blood flow to the brain.
Although the exact cause is not known it is thought to occur due to problem in nerve signaling and muscle contraction of face and neck region. It is often associated with neck and upper back spasm with pain radiating to the top of the head and the forehead. A poor posture, sitting at a desk or in front of a computer and psychological stress may be contributing factors.
Trigeminal autonomic cephalalgia consists of cluster headache, paroxysmal hemicrania and the SUNCT syndrome. The main symptoms are severe headache with redness of eyes and running nose.
Treatment of Headaches
The type of headache determines the treatment required. Often headaches resolve spontaneously without causing any other disturbance and not requiring any specific treatment. There are different headache drugs that are used depending upon the cause namely :
- Non-steroidal anti-inflammatory drugs (NSAIDs)
- Ergot derivatives
- Beta blockers
- Calcium channel blocker (high blood pressure medicine)
Surgery is required in some cases along with drugs. These cases include :
- Brain tumor
- Arteriovenous malformation (AVM)