HEADACHE

A headache or cephalalgia is pain anywhere in the region of the head or neck. It can be a symptom of a number of different conditions of the head and neck.
The brain tissue itself is not sensitive to pain as it lacks pain receptors . Rather, the pain is caused by disturbance of the pain- sensitive structures around the brain. Nine areas of the head and neck have these pain- sensitive structures, which are the cranium (the periosteum of the skull), muscles, nerves , arteries and veins , subcutaneous tissues , eyes, ears , sinuses and mucous membranes . There are a number of different classification systems for headaches. The most well-recognized is that of the International Headache Society. Headache is a non-specific symptom, which means that it has many possible causes. Treatment of a headache depends on the underlying cause, but commonly involves pain killers .

Cause

There are more than 200 types of headaches. Some are harmless and some are life-threatening. The description of the headache and findings on neurological examination, determine whether additional tests are needed and what treatment is best.

Primary vs. secondary headaches

Headaches are broadly classified as "primary" or "secondary". Primary headaches are benign, recurrent headaches not caused by underlying disease or structural problems. For example, migraine is a type of primary headache. While primary headaches may cause significant daily pain and disability, they are not dangerous. Secondary headaches are caused by an underlying disease, like a tumor, brain bleed or infection. Secondary headaches can be harmless or dangerous. Certain "red flags" or warning signs indicate a secondary headache may be dangerous.

Primary headaches

90% of all headaches are primary headaches. Primary headaches usually first start when people are between 20 and 40 years old .The most common types of primary headaches are migraines and tension-type headaches. [5] They have different characteristics. Migraines typically present with pulsing head pain, nausea photophobia (sensitivity to light) and phonophobia (sensitivity to sound). Tension- type headaches usually present with non- pulsing “bandlike” pressure on both sides of the head, not accompanied by other symptoms. [6] Other very rare types of primary headaches include:
cluster headaches : short episodes (15– 180 minutes) of severe pain, usually around one eye, with autonomic symptoms (tearing, red eye, nasal congestion) which occur at the same time every day. Cluster headaches can be treated with triptans and prevented with prednisone ergotamine or lithium.
trigeminal neuralgia: shooting face pain
hemicrania continua: continuous unilateral pain with episodes of severe pain Hemicrania continua can be relieved by the medication indomethacin primary
stabbing headache: recurrent episodes of stabbing “ice pick pain” or “jabs and jolts” for 1 second to several minutes without autonomic symptoms (tearing, red eye, nasal congestion). These headaches can be treated with indomethacin .
primary cough headache: starts suddenly and lasts for several minutes after coughing sneezing or straining (anything that may increase pressure in the head). Serious etiologies(see secondary headaches red flag section) must be ruled out before a diagnosis of “benign” primary cough headache can be made.
primary exertional headache: throbbing, pulsatile pain which starts during or after exercising, lasting for 5 minutes to 24 hours. The mechanism behind these headaches is unclear, possibly due to straining causing veins in the head to dilate, causing pain. These headaches can be prevented by not exercising too strenuously and can be treated with medications such as indomethacin .
primary sex headache: dull, bilateral headache that starts during sexual activity and becomes much worse during orgasm. These headaches are thought to be due to lower pressure in the head during sex. It is important to realize that headaches that begin during orgasm may be due to a subarachnoid hemorrhage, so serious causes must be ruled out first. These headaches are treated by advising the person to stop sex if they develop a headache. Medications such as propranolol and diltiazem can also be helpful.
hypnic headache: moderate-severe headache that starts a few hours after falling asleep and lasts 15–30 minutes. The headache may recur several times during night. Hypnic headaches are usually in older women. They may be treated with lithium.

Secondary headaches

Headaches may be caused by problems elsewhere in the head or neck Some of these are not harmful, such as cervicogenic headache (pain arising from the neck muscles). Medication overuse headache may occur in those using excessive painkillers for headaches paradoxically causing worsening headaches. [2] More serious causes of secondary headaches include:
meningitis : inflammation of the meninges which presents with fever and meningismus, or stiff neck bleeding inside the brain ( intracranial hemorrhage ) subarachnoid hemorrhage (acute, severe headache, stiff neck WITHOUT fever) ruptured aneurysm , arteriovenous malformation , intraparenchymal hemorrhage (headache only)
brain tumor : dull headache, worse with exertion and change in position accompanied by nausea and vomiting Often, the person will have nausea and vomiting for weeks before the headache starts.
temporal arteritis : inflammatory disease of arteries common in the elderly (average age 70) with fever, headache weight loss, jaw claudication, tender vessels by the temples, polymyalgia rheumatica acute closed angle glaucoma (increased pressure in the eyeball) headache that tarts with eye pain, blurry vision, associated with nausea and vomiting. On physical exam, the person will have a red eye and a fixed, mid dilated pupil.