25 - Migraine/Headache Flashcards
Pathophysiology of migraine
- Complex phenomenon – vascular theory (vasodilation of cerebral vasculature = headache; vasoconstriction = aura) is no longer appropriate on its own
- Is a neurological disorder
- Cortical spreading depression phenomenon (CSD) thought to -> cause migraine aura, activate trigeminal nerve afferents, and disrupt blood-brain barrier permeability
- Sensitization (peripheral and central) -> nerves become more responsive to stimuli
- Know that activation of serotonin receptors is key for acute migraine tx, but we don’t really know why (many theories)
Migraine subtypes
- Acute or “episodic” migraine w/ or w/o aura
- Chronic migraine w/ or w/o aura
Diagnostic criteria – acute migraine w/o aura **know this
- At least 5 attacks fulfilling criteria 2 through 4
- Headache attacks lasting 4 to 72 h (untreated or unsuccessfully treated)
- Headache has at least 2 of the following characteristics -> unilateral location, pulsating quality, moderate or severe pain intensity, aggravation by or causing avoidance of routine physical activity
- During headache at least 1 of the following -> N, V, or both; photophobia and phonophobia
Diagnostic criteria – acute migraine w/ aura **know this
- At least 2 attacks fulfilling criterion 2 and 3
- One or more of the following fully reversible aura sx:
- Visual -> flickering lights, flashes, lines/shapes, spots
- Sensory -> tingling and/or numbness of 1 limb, side of face and/or mouth/tongue
- Speech and/or language -> aphasia/dysphasia, word-finding
- Motor -> muscle weakness, loss of function
- Brainstem -> dizziness, loss of balance
- Retinal -> partial visual loss - At least 2 of the following 4 characteristics:
- At least 1 aura sx spreads gradually over 5 or more minute, and/or 2 or more sx occur in succession
- Each individual aura sx lasts 5-60 mins
- At least 1 aura sx is unilateral
- Aura is accompanied, or followed w/in 60 mins, by headache
Diagnostic criteria – chronic migraine w/ or w/o aura **know this
- Headache (tension-type-like and/or migraine-like) on 15 or more days/month for > 3 months and fulfilling criteria 2 and 3
- Occurring in a pt who has had at least 5 attacks fulfilling criteria 2-4 for “acute migraine w/o aura” and/or criteria 2 and 3 for “acute migraine w/ aura”
- On 8 or more days/month for > 3 months, fulfilling any of the following:
- Criteria 3 and 4 for “acute migraine w/o aura”
- Criteria 2 and 3 for “acute migraine w/ aura”
- Believed by the pt to be migraine at onset and relieved by a triptan or ergot derivative
Migraine phases
- Phase 1 = prodrome
- Phase 2 = aura
- Phase 3 = early headache
- Phase 4 = late headache
- Phase 5 = postdrome
Premonitory sx (prodrome)
- ~24-48 h before onset of headache
- Neurologic sx (ex: allodynia, phonophobia, photophobia, hypersomnia, and difficulty concentrating)
- Psychological (ex: anxiety, depression, euphoria, drowsiness, fatigue)
- Autonomic (ex: polyuria, diarrhea, constipation)
- Constitutional (ex: stiff neck, yawning, thirst, food cravings)
Describe phase 2 (aura)
- Can precede and/or be present during headache
- Lasts < 60 mins
- Completely reversible
- Mix of positive and negative focal neurological sx (not just visual and sensory):
- Visual -> positive = flickering lights, spots, lines; negative = loss of vision
- Sensory -> positive = pins and needles; negative = numbness
Characteristics of a typical migraine headache **know this
- Unilateral (most often), but not always on the same side
- Throbbing, pulsating
- Attack progressively worsens over hours
- Often N and V (vomiting less common)
- Photophobia/ phonophobia (very common) -> often migraine sufferer will need to rest in dark, quiet room b/c of this
- Osmophobia and cutaneous allodynia
Red flag migraine sx
- Age of onset > 50 y/o
- Severe and abrupt onset
- Sx worsening over days/weeks
- Neurologic signs -> stiff neck, focal signs, reduced consciousness, abnormal speech, cognitive impairment
- Systemic signs -> fever, rash, N/V
- New onset cancer, lyme disease, HIV
- Triggered by cough, exertion, sexual activity
Migraine and stroke risk
**Take home message = women who have migraine w/o aura and no other risk factors for stroke may use a contraceptive pill w/ < 50 mcg estrogen; women who have migraine w/ aura should be encouraged to stop smoking, control their BP, and use an alternative method of contraception
Potential migraine triggers
- Most common = emotional stress, hormones in women, not eating, weather, sleep disturbances
- Moderately common = odours, neck pain, lights, alcohol, smoke, sleeping late, heat, food
- Less common = exercise, sexual activity
Non-pharms for migraine
- *Avoid triggers, hydration, maintain routine
- Rest/sleep in dark, quiet room
- Headache diary
- Stress management
- Cold/heat packs
- Regular meals, caffeine balance
Pharmacotherapy options for migraine
- Acute drug treatment (abortive medications, “relievers”) -> taken prn for headache sx
- Preventative drug tx -> aim to decrease migraine frequency; taken on a regular basis
Goals of acute therapy
- Relieve pain and associated sx of migraines
- Functional headache-free state in 2 h w/ no recurrence in 24 h
- Minimal or no adverse effects
- Relieve migraine-related disability so that pt can return quickly to normal function
- Avoid medication overuse headache and development of central sensitization (when abortive medications are less effective; can be prevented w/ early tx)
Benefit to treating the headache early
- Early tx reduces overall burden of migraine (and reduces likelihood of central sensitization)
- Challenges:
- Some avoid medication unless headache is severe b/c of cost and SE
- Some w/ frequent attacks limit acute medication for fear of overuse
Migraine – acute pharmacotherapy options
- Triptans (5-HT receptor agonists) *migraine specific
- Ergot derivatives (nonselective 5-HT agonist) *migraine specific
- NSAIDs, acetaminophen
- Domperidone, metoclopramide, prochlorperazine (anti-emetic)
- *Best if taken early in attack (ie: at onset of head pain); taking at aura may be too soon
Triptans for migraine (role, efficacy, MOA, CI)
- Role -> moderate to severe migraine attacks (1st line)
- Don’t seem as effective if taken during aura (take at pain onset)
- All effective in reducing N/V, photo and phonophobia
- 1/3 of px may not respond to triptan -> may benefit from switching to a different triptan (space 24 h)
- MOA in migraine unclear (vasoconstrictor but also inhibits neurogenic inflammation peripherally and prevents central sensitization)
- CI in px w/ CAD (despite evidence to suggest safe use)
- Can use SC, ODT, or intranasal formulations if headache builds rapidly or is accompanied by early N/V; more expensive
- All triptans require dose adjustment in liver dysfunction (some CI); some require dose adjustment in renal dysfunction
Drug-drug interactions w/ triptans
- Don’t take w/in 24 h of ergot alkaloid (additive vasoconstriction)
- Avoid w/in 2 weeks of MAOIs
- Caution w/ SSRI/SNRI (serotonin syndrome rare)
- CYP3A4 inhibitors
- Propranolol can increase serum concentrations of certain triptans (mostly rizatriptan, so reduce dose if needed)
Triptans SE
- Common = paresthesia’s, fatigue, dizziness, flushing, warm sensations, somnolence
- “Triptan sensations” = mild and transient burning, tingling, tightness, pressure, pain in face/chest/neck/throat
- Serious but rare = MI, coronary vasospasm w/ ischemia, serotonin syndrome
- CI = cerebrovascular disease, IHD (angina, post-MI), uncontrolled HTN, PVD, hemiplegic or basilar migraine
Ergots for migraine (role, MOA)
- 1st line for severe/ultra-severe attacks
- Non-selective 5-HT agonist
- Also, alpha + beta-adrenergic agonist and dopamine D1 + D2 agonist (contributes to SE rather than migraine relief)
- Brand name = migranal (dihydroergotamine)
- Slower onset of action and less migraine recurrence than sumatriptan SC/IN
- More N/V (pre-dose w/ antiemetic) but less chest pain than triptans
Ergots SE
- Common = N/V, abdominal pain, weakness, fatigue, muscle pain, diarrhea
- Serious = severe peripheral ischemia (cold, numb, painful extremities), gangreneous extremities, MI, hepatic necrosis, bowel and brain ischemia
- CI = cardiac/ cerebrovascular disease, uncontrolled HTN, pregnancy, hemiplegic or basilar migraine
- Don’t use w/in 12 h of triptans
Acetaminophen for migraine (role, efficacy)
- Role -> acute migraine tx of mild to moderate severity; pt w/ CI or intolerance to NSAIDs
- Best if taken early
- May be less effective than NSAIDs, but superior to placebo
NSAIDs for migraine (MOA, role, SE, caution)
- Prevents inflammation in the trigeminovascular system via prostaglandin synthesis inhibition
- Role -> acute migraine tx of mild to moderate severity
- Can use alone or w/ metoclopramide 10 mg
- SE = GI (dyspepsia, N/V, diarrhea), bleed, renal, rash
- Avoid or caution in ulcer disease, gastritis/ esophagitis, renal disease, hypersensitivity