Migraine

What is a Migraine?

• A migraine is a severe painful headache that is often preceded or accompanied by sensory warning signs such as flashes of light, blind spots, tingling in the arms and legs, nausea, vomiting, and increased sensitivity to light and sound. The excruciating pain that migraines bring can last for hours or even days.

History of Migraines

• Have been with us for at least 7,000 years. • In ancient Greece, Galen attributed these painful

headaches as “ascent of vapors” or humors from the liver to the brain. He called them Hemicranias.

• Hemicrania Megrim Migraine• In the 17th century, the idea of rising humors was

replaced by increased blood flow.• In the 1980s, Harold G. Wolff of New York-

Presbyterian Hospital, said that migraine pain stems from the dilation and stretching of brain blood vessels, leading to the activation of pain-signaling neurons.

What Actually Happens During a Migraine?

THEORIES

• Vascular Theory Brain Scans suggest that Migraines arise from an increase in blood flow of about 300% preceding the headache. • Neurogenic Theory Spreading depression of cortical electrical activity followed by vascular phenomena.

4 PHASES OF A MIGRAINE

• Prodrome• Aura•Headache• Postdrome

Cortical Spreading Depression

• Wave of hyperactivity followed by a wave of inhibition and it usually occurs in the visual cortex.

• 2-6mm per wave• This is what is thought to happen

during migraines with aura.

Neurogenic Inflammation

Retrograde Transmission In Afferent Nerves

Release of Mediators(5-HT,Neurokinin,SubstanceP,CGRP,NO)

Vascular Phenomena

Prodrome

• Stage of Migraine that is characterized by difficulty concentrating, yawning, fatigue and/or sensitivity to light and noise.

• Duration: A few hours to a few days

Aura

• Stage of migraine that is characterized by visual illusions of sparks and lights, often followed by blind or dark spots in the same place as the bright hallucinations

• Duration: 20-60 minutes

Headache

• Stage characterized by excruciating or throbbing pain along with sensitivity to light and sound.

• May be accompanied by nausea and vomiting

• Sometimes only half of the head or part of the head is in pain.

• Duration: 4 – 72 hours

Postdrome

Characterized by:• sensitivity to light and

movement• Lethargy• Fatigue• Difficulty focusing• Also called a “zombie phase”• Duration: A few hours to a few

days

Ways to Treat Migraines

• Avoiding Trigger Factors• Simple Non-Drug Treatment • Pain Medications• Prophylactic Medications• “Abortive Medications” (acute, specific medications)

Avoiding Trigger Factors

• For reasons unknown, migraines can be set of by many factors like alcohol, perfume, dehydration, excessive exercise, menstruation, stress, weather changes, seasonal changes, allergies, lack of sleep, altitude, flickering lights and hunger.

Simple Non-Drug Treatments

• Ice to head• Heat to head• Massages

Drug Therapy

Drug Therapy has to be Induvidualized based on• Severity • Frequency of Attacks• Response of an Induvidual to a Drug

Based on Severity and Frequency the attacks can be classified into Mild Migraine Moderate Migraine Severe Migraine

Mild MigraineCases having fewer than oneattack per month of throbbing but

tolerableheadache lasting upto 8 hours

Medications: Simple analgesics like Paracetamol (0.5–1 g) or aspirin (300–600 mg) Nonsteroidal antiinflammatory drugs(NSAIDs) and their

combinations• Ibuprofen (400–800 mg 8 hourly), • Naproxen (500mg followed by 250 mg 8 hourly),• Diclofenac(50 mg 8 hourly),• Mephenamic acid (500 mg 8 hourly)

Antiemetics• Metoclopramide (10 mg oral/i.m.)• Domperidone(10–20 mg oral) • Prochlorperazine (10–25 mg oral/i.m.)

Moderate MigraineThrobbing headache is more intense, lasts for 6–24 hours, nausea/vomiting

andother features are more prominent and the patient is functionally impaired.

Simple Analgesics are not Effective so Stronger NSAID’S are used.

Specific Drugs like Triptans and Ergot Preparations with AntiEmetics are used.

Severe Migraine2–3 or more attacks per month of severe throbbing

headache lasting 12–48 hours

Analgesics/NSAIDs and their combinationsusually do not afford adequate relief. So Specific AntiMigraine Drugs are used such as

Ergotamine Dihydroergotamine Sumatriptan Rizatriptan..,etc

Ergotamine(Oral/Sublingual)

• Most Effective Ergot Alkaloid for Migraine. • Given Early in attack, Relief is often Dramatic and

Lower Doses Suffice

M/A: Ergotamine acts by constricting the dilated cranial vessels and/or by specific constriction of carotid A-V shunt channels• These actions appear to be mediated through partial

agonism at 5-HT1D/1B receptors in and around cranial vessels.

• Dihydroergotamine (DHE) preferred for parenteral administration because injected DHE is less hazardous.

Triptans(Selective 5-HT1D/1B agonists)

• First Line Drugs for Patients who Fail to Respond to Analgesics

Ex: Sumatriptan,Rizatriptan,

Sumatriptan

• Sumatriptan is as effective and better tolerated than ergotamine.

M/A:• Antimigraine activity of sumatriptan has been

ascribed to 5-HT1D/1B receptor mediated constriction of dilated cranial blood vessels, especially the arterio-venous shunts in the carotid artery, which express 5-HT1D/1B receptors.

• Dilatation of these shunt vessels during migraine attack is believed to divert blood flow away from brain parenchyma.

• Pharmacokinetics - Sumatriptan is absorbed rapidly and completely after s.c. injection. Oral bioavailability averages only 15%.

Side effects - Tightness in head and chest, feeling of heat and other paresthesias in limbs, dizziness, weakness are short lasting, but dose related side effects

• Contraindications - Ischaemic heart disease,hypertension, epilepsy, hepatic or renal impairment and pregnancy are the contraindications. Patients should be cautioned not to drive

PROPHYLAXIS OF MIGRAINE

Regular medication to reduce the frequency and/or severity of attacks is recommended for moderate-to-severe migraine when 2–3 or more attacks occur per month.

B-Adrenergic blockers (Propranolol,Timolol, metoprolol, atenolol)

Tricyclic antidepressants (Amitriptyline) Calcium channel blockers (Verapamil,Flunarizine) Anticonvulsants (Valproic acid and Gabapentin) 5-HT antagonists (Methysergide and

Cyproheptadine)

β-Adrenergic blockers

• Propranolol is the most commonly used drug: reduces frequency as well as severity of attacks in upto 70% patients

• The starting dose is 40 mg BD, which may be increased upto 160 mg BD if required.

• Nonselective (timolol) • β1 selective (metoprolol, atenolol) agents are

also effective.• Pindolol and others having intrinsic

sympathomimetic action are not useful.

Tricyclic antidepressants

Amitriptyline (25–50 mg at bed time)Produces more side effects than

propranololAntimigraine effect is independent of

antidepressant property better suited for patients who suffer

from depression.

Calcium channel blockers

• Verapamil• Flunarizine• Frequency of attacks is often reduced• claimed to be a cerebro-selective Ca2+

channel blockerreducing intracellular Ca2+ overload due to brain hypoxia and other causes.

• Side effects : sedation, constipation, dry mouth, hypotension, flushing,weight gain and rarely extrapyramidal symptoms

Anticonvulsants

• Valproic acid (400–1200mg/day)• Gabapentin (300–1200 mg/day)• Topiramate• Efficacy of anticonvulsants in migraine

is lower than that of β blockers.• Indicated in patients refractory to

other drugs or when propranolol is contraindicated.

5-HT antagonists

• The prophylactic effect of methysergide and cyproheptadine is less impressive than β Blockers.

• They are rarely used now for migraine

Hey My Migraine is

Goneeeee!!!!!..