Migraine is a neurological syndrome characterized by altered bodily perceptions, severeheadaches,and nausea.Physiologically, the migraine headache is a neurological condition morecommon to women than to men. The word migrainewas borrowed from Old French migraine(originally as "megrim", but respelled in 1777 on a contemporaryFrench model). The French term derived from a vulgarpronunciation of the Late Latin word hemicrania,itself based on Greek hemicrania,from Greek roots for "half" and "skull".
The typical migraine headache is unilateral (affecting one half of thehead) and pulsating, lasting from 4 to 72 hours; symptoms include nausea, vomiting, photophobia(increased sensitivity to light), and phonophobia(increased sensitivity to sound).Approximately one-third of people who suffermigraine headache perceive an aura—unusualvisual, olfactory, or other sensory experiences that are a sign that themigraine will soon occur.
Initial treatment is with analgesics for the headache, an ant emeticfor the nausea, and the avoidance of triggering conditions. The cause ofmigraine headache is unknown; the most common theory is a disorder of the serotonergiccontrol system.
There are migraine headache variants, some originate in the brainstem(featuring intercellular transport dysfunction of calcium and potassium ions)and some are genetically disposed. Studies of twins indicate a 60 to 65 percentgenetic influence upon their propensity to develop migraine headache. Moreover,fluctuating hormone levels indicate a migraine relation: 75 percent of adultpatients are women, although migraine affects approximately equal numbers ofprepubescent boys and girls; propensity to migraine headache is known todisappear during pregnancy, although in some women migraines may become morefrequent during pregnancy.
Rodents can be grown that suffer from the condition.
Signs and symptoms
The signs and symptoms of migraine vary among patients. Therefore, what apatient experiences before, during and after an attack cannot be definedexactly. The four phases of a migraine attack listed below are common but notnecessarily experienced by all migraine sufferers. Additionally, the phasesexperienced and the symptoms experienced during them can vary from one migraineattack to another in the same migraineur
- The prodrome, which occurs hours or days before the headache.
- The aura, which immediately precedes the headache.
- The pain phase, also known as headache phase.
- The postdrome.
Prodromal symptoms occur in 40–60% of migraineurs (migraine sufferers).This phase may consist of altered mood, irritability, depression or euphoria, fatigue, yawning,excessive sleepiness, craving for certain food (e.g. chocolate),stiff muscles (especially in the neck), constipation or diarrhea, increasedurination, and other visceral symptoms. These symptoms usually precede theheadache phase of the migraine attack by several hours or days, and experienceteaches the patient or observant family how to detect that a migraine attack isnear.
For the 20–30% of migraine sufferers who experience migraine with aura,this aura comprises focal neurological phenomena that precede or accompany theattack. They appear gradually over 5 to 20 minutes and generally last fewerthan 60 minutes. The headache phase of the migraine attack usually beginswithin 60 minutes of the end of the aura phase, but it is sometimes delayed upto several hours, and it can be missing entirely. Symptoms of migraine aura canbe visual, sensory, or motor in nature.
Visual aura is the most common of the neurological events.There is a disturbance of vision consisting usually of unformed flashes ofwhite and/or black or rarely of multicolored lights (photopsia) orformations of dazzling zigzag lines (scintillating scotoma; often arranged likethe battlementsof a castle, hence the alternative terms "fortification spectra" or"teichopsia"). Some patients complain of blurred or shimmering orcloudy vision, as though they were looking through thick or smokedglass, or, in some cases, tunnelvision and hemianopsia. The somatosensoryaura of migraine consists of digitolingual or cheiro-oral paresthesias,a feeling of pins-and-needles experienced in the hand and arm as well as in thenose-mouth area on the same side. Paresthesias migrate up the arm and thenextend to involve the face, lips and tongue.
Other symptoms of the aura phase can include auditory or olfactoryhallucinations, temporary dysphasia, vertigo,tingling or numbness of the face and extremities, and hypersensitivity totouch.
The typical migraine headache is unilateral, throbbing, and moderate tosevere and can be aggravated by physical activity. Not all these features arenecessary. The pain may be bilateral at the onset or start on one side andbecome generalized, and usually it alternates sides from one attack to thenext. The onset is usually gradual. The pain peaks and then subsides andusually lasts 4 to 72 hours in adults and 1 to 48 hours in children. Thefrequency of attacks is extremely variable, from a few in a lifetime to severala weeks, and the average migraineur experiences one to three headaches a month.The head pain varies greatly in intensity.
The pain of migraine is invariably accompanied by other features. Nausea occurs inalmost 90 percent of patients, and vomiting occurs in about one third ofpatients. Many patients experience sensory hyperexcitability manifested by photophobia,phonophobia,and osmophobiaand seek a dark and quiet room. Blurred vision, nasal stuffiness, diarrhea, polyuria, pallor, or sweatingmay be noted during the headache phase. There may be localized edema of the scalp orface, scalp tenderness, prominence of a vein or artery in the temple, orstiffness and tenderness of the neck. Impairment of concentration and mood arecommon. The extremities tend to feel cold and moist. Vertigomay be experienced; a variation of the typical migraine, called vestibular migraine, has also been described.Lightheadedness, rather than true vertigo and a feeling of faintness may occur.
The patient may feel tired or "hung-over" and have head pain,cognitive difficulties, gastrointestinal symptoms, mood changes, and weakness.Some people feel unusually refreshed or euphoric after an attack, whereasothers note depression and malaise. Often, some of the minor headache phase symptoms maycontinue, such as loss of appetite, photophobia, and lightheadedness. For somepatients, a 5- to 6-hour nap may reduce the pain, but slight headaches maystill occur when the patient stands or sits quickly. These symptoms may go awayafter a good night's rest, although there is no guarantee. Some people maysuffer and recover differently than others.