MIGRAINE
Def It is paroxysmal often familial disorder characterized by throbbing headache (usually unilateral) associated with autonomous manifestations (e.g. nausea &vomiting).
It may be preceded by visual ,sensory , and/or motor manifestations.
Aetiology:
1-Herido-Familial(70%)
2-Females more than males (2:1)
3-onset around puberty
4-more in urban inhabitants (psychological stress)
5-more in obsessive perfectionistic persons
6-precipitated by mental and physical exhaustion , menses or certain diets
e.g.: chocolate , cheese , nuts and excessive smoking or alcohol
C/P OF CLASSIC MIGRAINE
1-Prodroma : drowsiness,fatigue or hunger may occur several days before the attacks
2-Aura : immediately before the attack
(a)Visual Disturbances: as Scotomas flashes of light , zig-zags(fortifications)
or hemianopia (nos el shasha mesh shayef)
(b)Motor or Sensory manifestations: e.g.weakness,aphasia or paraethesias
*The manifestations of the AURA are present on the opposite side of the coming headache
3-Headache:
(a)It occurs in periodic and recurrent attacks
(b)It starts in the temple or around the eye
(c)Spreads to involve the whole side of the head
(d)It is throbbing
(e)It is with bright light & excitement
(f)Passes away with sleep
(g)It lasts for several hours or days
(h)Assosciating with nausea( occasionally vomiting,palor,coldness of the face and extremities
(i)May be followed by polyurea
MECHANISM *the manifestations of the aura are due to VC of the cerebral areteries while the
headache is due to subsequent reactive VD
*there are 2 theories which explain these vascular changes:
1) SEROTININ(5-HT) THEORY: -an initial increase in blood serotonin level
leads to its action on the sereotinin receptors
(5-HT1 receptors)irin the smooth muscles of the cerebral
blood vessels,resulting in their constriction (aura)
-Degeradation of serotonin and dec. of its
blood levels follows,resulting in cerebral vd(headache)
-The serotonin receptors in other parts of the body(5-HT2 &
5-HT3 receptors) are similarly affected,resulting in
extracerebral vascular changes and activation of some
autonomic reflexes (nausea and vomiting)
2-CALCIUM-UPTAKE THEORY (HYPOXIC THEORY):
The onset of migraine is due to a focal cerebral hypoxia assosciated with the rapid entry of ca
Into the brain cells and into the smooth muscles cells of the cerebral arteries,this causes the
Constriction of these arteries (aura)with reactive dilatation(headache)
IMPORTANT TYPES
1)Classic Migraine : always preceded by an aura (10% of the cases)
2)Common Migraine : The headache is not preceded by an aura as the vasoconstrictve phases
is not severe.this is the most frequent type of migraine (80% of cases)
3)Opthalmoplegic Migraine:Severe migraine followed within days by transient paralysis of
ocular muscles , external and internal opthalmoplegia
4)Facial Migraine: Migraine assosciated with transient facial paralysis
5)Hemiplegic Migraine: Migraine with transient hemiplegia
6)Basilar artery Migraine:It occurs in young females and is often related to menses.
The prodroma includes visual disturbances , quickly followed by
Vertigo , ataxia and/or dysarthria .this is followed by severe occipital
headache and vomiting.
*CLUSTER HEADACHE:(HORTON's Syndrome,Histamine Cephalgia):
1-These are attacks of sever agonising headache starting on one side in the orbital and
frontal regions , and spreading gradually to the same side of the head and neck.
The headache is usually ass. With conjunctival injection,lacrimation,rhinorrhea,flushing
and sweating of the face on the affected side.there is NO nausea or vomiting as seen in
other forms of migraine
2-The attack of headache is brief (several minutes 1 hour) and usually occurs during night
90% of cases occur in middle aged males
4-The attacks are characterized by their regularity and occurrence in clusters i.e. every 24
hours for few weeks or months.The clusters are followed by long period (up to 6 months or
1 year),where the patients are completely free.
5-The attacks are ppt.by alcoholic beverages and injection of histamine.They are aggravated
by application of heat and relieved by cold.
TREATMENT:
(A)DURING THE ATTACK :
1-Ask the patient to try to relax in a dark quite room ,mild attacks may be relieved if the patient
can sleep
2-Sumatriptan
i It acts selectively on the serotonin (5-HT1)receptors in the cerebral
blood vessels leading to their VC & relief of the headache , the blood vessels in
other parts of the body are not affected.
Thus,Sumatriptan does NOT have the side effects of ergotamine which
acts on the serotonin receptors allover the body.
ii- Dose: - 6mg S.C. may be repeated after 2 hrs. max. dose 12 mg/day
- 100mg orally (1 tab.) may be repeated after 2 hrs. max dose 300 mg/day
(C.I.) *It is not used in prophylaxis and like most drugs it is better avoided in HTN , pregnancy &
ischemic heart diseases.
3-Analgesics:as paracetamol , optalidon
4-Antiemetics for vomiting as Metoclopormide primperan)in suppository form.
(B)DURING THE ATTACKS:
1-Avoid ppt. factors if present.
2-Flunarizine HCl (sibelium):
*Dose:10mg(2 capsules) daily before sleep for 6 months
*Side effects:depression,coma,extrapyramidal disorders,weight gain.
3-Pizotifen(sandomigran):a serotonin antagonist (1 tablet t.d.s.).
4-propranolol(inderal): Beta blocker,it prevents the uptake of adrenaline by beta receptors in the
vessel wall,Thus preventing vasodilatation.it is best given in common
migraine where the V.C.phase is minimal
5-Other Measures include:
a) Antihistaminics in cluster headache
b) Antidepressants
c) Diuretics
d) Antiepileptics
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