Migraine
Summary
Migraine is a primary headache disorder characterised by recurrent episodes of moderate-to-severe headache, typically unilateral, pulsating, and associated with nausea, photophobia, and phonophobia. Attacks last 4-72 hours and are often disabling. Approximately one-third of patients experience aura (usually visual) preceding the headache. Diagnosis is clinical using ICHD-3 criteria. Acute treatment includes simple analgesics, triptans, and anti-emetics. Prophylaxis is indicated for frequent or disabling attacks and options include beta-blockers, amitriptyline, topiramate, and CGRP inhibitors. Medication overuse headache is a common complication of excessive acute medication use.
Key Facts
- Definition: Recurrent primary headache with specific clinical features (ICHD-3)
- Incidence: 12-15% prevalence; most common neurological disability
- Demographics: F:M 3:1; peak prevalence 25-55 years
- Pathognomonic: Unilateral, pulsating, moderate-severe + nausea/photo-phonophobia
- Gold Standard Investigation: Clinical diagnosis (ICHD-3); imaging if red flags
- First-line Treatment: Acute: NSAIDs/paracetamol ± triptan; Prevention: propranolol/amitriptyline/topiramate
- Prognosis: Chronic condition; often improves with age
Clinical Pearls
Triptan Pearl: Triptans work best taken early in attack (when pain is still mild). Avoid in uncontrolled hypertension, cardiovascular disease, or previous stroke.
MOH Pearl: Medication overuse headache occurs with regular use of simple analgesics greater than 15 days/month or triptans/opioids greater than 10 days/month.
Aura Pearl: Typical visual aura develops over 5+ minutes and lasts 5-60 minutes. Sudden onset suggests alternative diagnosis (e.g., TIA, seizure).
CGRP Pearl: CGRP monoclonal antibodies (erenumab, fremanezumab, galcanezumab) are a game-changer for refractory migraine prophylaxis.
Diary Pearl: A headache diary is invaluable for diagnosis, identifying triggers, monitoring treatment response, and detecting MOH.
Why This Matters Clinically
Migraine is extremely common and a leading cause of disability worldwide. Most cases are managed in primary care. Distinguishing migraine from secondary headaches, appropriate acute treatment, and recognising when prophylaxis is needed are essential skills.
Prevalence
| Statistic | Value |
|---|---|
| Global prevalence | 12-15% |
| Female:Male ratio | 3:1 |
| Peak age | 25-55 years |
| Childhood prevalence | 5-10% (equal sex ratio) |
Risk Factors
| Factor | Association |
|---|---|
| Female sex | 3x higher risk |
| Family history | Strong genetic component (50-60% heritability) |
| Age | Peak in reproductive years |
| Comorbidities | Depression, anxiety, epilepsy |
Common Triggers
| Category | Triggers |
|---|---|
| Hormonal | Menstruation, oestrogen withdrawal, OCP |
| Dietary | Alcohol (especially red wine), cheese, chocolate, caffeine withdrawal |
| Environmental | Bright lights, loud noise, strong smells |
| Lifestyle | Stress, poor sleep, skipped meals, dehydration |
| Medication | GTN, dipyridamole |
Mechanism Overview
Step 1: Trigger Activation
- Cortical spreading depression (CSD) in aura
- Activation of trigeminovascular system
Step 2: Trigeminovascular Activation
- Trigeminal nerve fibres release CGRP, substance P, neurokinin A
- Vasodilation of meningeal vessels
- Neurogenic inflammation
Step 3: Pain Transmission
- Pain signals via trigeminal ganglion to trigeminal nucleus caudalis
- Ascending to thalamus and cortex
- Activation of brainstem autonomic centres
Step 4: Central Sensitisation
- Abnormal pain processing
- Cutaneous allodynia (scalp tenderness)
- Contributes to chronification
Aura
- Cortical spreading depression (CSD)
- Wave of neuronal depolarisation followed by inhibition
- Starts occipitally → visual symptoms
- Spreads anteriorly → sensory/motor symptoms
Key Mediators
| Mediator | Role |
|---|---|
| CGRP | Vasodilation, neurogenic inflammation; therapeutic target |
| Serotonin (5-HT) | Triptan target (5-HT1B/1D receptors) |
| Substance P | Pain transmission |
| Dopamine | Nausea, yawning in prodrome |
Migraine Without Aura (80%)
ICHD-3 Criteria: A. At least 5 attacks fulfilling B-D B. Headache lasting 4-72 hours (untreated) C. At least 2 of:
Migraine With Aura (20-30%)
Typical Aura:
Visual Aura (most common):
Sensory Aura:
Migraine Phases
| Phase | Duration | Features |
|---|---|---|
| Prodrome | Hours to 2 days | Mood changes, food cravings, yawning, fatigue, neck stiffness |
| Aura | 5-60 minutes | Visual, sensory, speech symptoms |
| Headache | 4-72 hours | Typical migraine features |
| Postdrome | Hours to 2 days | Fatigue, cognitive dulling, mood changes |
Red Flags (SNOOPING)
[!CAUTION]
- Systemic symptoms (fever, weight loss)
- Neurological deficit
- Onset sudden (thunderclap)
- Older age of onset (greater than 50)
- Pattern change (progressive, different from usual)
- Immunity compromised
- New headache in young child
- Growing worse despite treatment
Usually Normal
- Migraine is a clinical diagnosis with normal examination between attacks
During Attack
- Pallor
- Photophobia (avoids light)
- May have tenderness to head/neck palpation
Mandatory Checks
- Blood pressure
- Fundoscopy (papilloedema)
- Neurological examination (to exclude secondary causes)
When to Investigate
| Scenario | Action |
|---|---|
| Typical migraine, no red flags | No investigation needed |
| Red flag features | MRI brain (± MRA/V if vascular concern) |
| Thunderclap headache | CT head + LP (SAH) |
| New headache over 50 | ESR, CRP (GCA), imaging |
| Progressive headache | MRI to exclude mass lesion |
Headache Diary
Essential for:
- Confirming diagnosis
- Identifying triggers
- Assessing frequency and disability
- Monitoring treatment response
- Detecting medication overuse
Management Algorithm
MIGRAINE DIAGNOSIS (ICHD-3)
↓
┌──────────────────────────────────────────────────────────┐
│ ACUTE MANAGEMENT │
│ Mild-moderate: Simple analgesic (aspirin 900mg, │
│ ibuprofen 400-600mg, paracetamol 1g) │
│ + anti-emetic if needed │
│ Moderate-severe: Triptan (sumatriptan 50-100mg PO) │
│ + NSAID + anti-emetic │
│ Refractory: Consider SC sumatriptan, nasal spray │
└──────────────────────────────────────────────────────────┘
↓
┌──────────────────────────────────────────────────────────┐
│ ASSESS FOR PROPHYLAXIS │
│ Consider if: │
│ - 4+ migraine days/month │
│ - Disability with attacks │
│ - Acute treatment ineffective or overused │
│ - Patient preference │
└──────────────────────────────────────────────────────────┘
↓
┌──────────────────────────────────────────────────────────┐
│ PROPHYLAXIS OPTIONS │
│ FIRST-LINE: │
│ - Propranolol 40-160mg/day │
│ - Amitriptyline 10-75mg at night │
│ - Topiramate 50-100mg/day │
│ - Candesartan 8-16mg/day │
│ │
│ SECOND-LINE/REFRACTORY: │
│ - CGRP inhibitors (erenumab, fremanezumab) │
│ - Botulinum toxin (chronic migraine) │
│ - Sodium valproate (caution in women) │
└──────────────────────────────────────────────────────────┘
Acute Treatment
| Drug | Dose | Notes |
|---|---|---|
| Aspirin | 900mg PO | First-line; dispersible better |
| Ibuprofen | 400-600mg PO | First-line NSAID |
| Paracetamol | 1g PO | Less effective than NSAIDs |
| Sumatriptan | 50-100mg PO | First-line triptan |
| Sumatriptan | 6mg SC | Fastest onset; severe attacks |
| Zolmitriptan | 2.5-5mg PO/nasal | Alternative triptan |
| Metoclopramide | 10mg PO/IV | Anti-emetic + prokinetic |
| Prochlorperazine | 3mg buccal | Anti-emetic option |
Triptan Contraindications:
- Uncontrolled hypertension
- Coronary artery disease, previous MI
- Cerebrovascular disease
- Peripheral vascular disease
- Hemiplegic or basilar migraine
Prophylaxis
| Drug | Starting Dose | Target Dose | Notes |
|---|---|---|---|
| Propranolol | 40mg BD | 80-160mg/day | Avoid in asthma |
| Amitriptyline | 10mg nocte | 25-75mg | Sedation; good for sleep |
| Topiramate | 25mg nocte | 50-100mg/day | Weight loss; cognitive SE |
| Candesartan | 8mg OD | 16mg | ARB; good tolerability |
| Sodium valproate | 200mg BD | 400-600mg BD | Avoid in women of childbearing age |
CGRP Inhibitors
| Drug | Route | Frequency | Notes |
|---|---|---|---|
| Erenumab | SC | Monthly | 70-140mg |
| Fremanezumab | SC | Monthly or quarterly | 225mg monthly or 675mg quarterly |
| Galcanezumab | SC | Monthly | 120mg (loading 240mg) |
Medication Overuse Headache (MOH)
- Defined as: simple analgesics greater than 15 days/month or triptans/opioids greater than 10 days/month
- Treatment: abrupt or gradual withdrawal (with bridging therapy)
- Warn patients about MOH
| Complication | Features | Management |
|---|---|---|
| Medication overuse headache | Daily/near-daily headache | Withdrawal, prophylaxis |
| Chronic migraine | 15+ headache days/month for 3+ months | Prophylaxis, botox |
| Status migrainosus | Attack lasting greater than 72 hours | IV fluids, steroids, anti-emetics |
| Migrainous infarction | Aura symptoms with ischaemic stroke | Stroke management |
Natural History
- Chronic condition
- Often decreases with age (especially after menopause in women)
- 3-5% of episodic migraine transforms to chronic annually
Treatment Outcomes
- Acute treatment success: 60-80% with triptans
- Prophylaxis: 50% reduction in frequency in 50% of patients
Key Guidelines
-
NICE Guideline CG150. Headaches in over 12s — 2012 (updated 2021)
-
SIGN 155. Pharmacological management of migraine — 2018
-
AHS Consensus Statement on Migraine Preventive Treatment — 2021
-
ICHD-3. International Classification of Headache Disorders, 3rd edition — Headache Classification Committee
Key Evidence
CGRP Inhibitor Trials:
- Erenumab significantly reduces monthly migraine days
- PMID: 29132880
Botulinum Toxin (PREEMPT):
- Effective for chronic migraine
- PMID: 20816182
What is migraine?
Migraine is a brain condition that causes recurring episodes of severe headache, usually on one side, often with nausea and sensitivity to light and sound. It's not just a bad headache - it's a neurological disorder.
What causes it?
Migraine involves abnormal brain activity and changes in blood vessels. Triggers like stress, hormones, certain foods, or lack of sleep can set off an attack in susceptible people.
Treatment
- During an attack: Pain relief (aspirin, ibuprofen) or a migraine-specific tablet (triptan). Take early in the attack.
- Prevention: If attacks are frequent, we can prescribe a daily tablet to reduce them.
How can I help myself?
- Keep a headache diary to identify triggers
- Maintain regular sleep, meals, and hydration
- Avoid known triggers
- Don't overuse painkillers (this can worsen headaches)
-
NICE Guideline CG150. Headaches in over 12s: diagnosis and management. 2012.
-
Headache Classification Committee. The International Classification of Headache Disorders, 3rd edition (ICHD-3). Cephalalgia. 2018;38(1):1-211. PMID: 29368949
-
Goadsby PJ et al. A Controlled Trial of Erenumab for Episodic Migraine. N Engl J Med. 2017;377(22):2123-2132. PMID: 29132880
-
Dodick DW et al. OnabotulinumtoxinA for treatment of chronic migraine (PREEMPT). Cephalalgia. 2010;30(7):793-803. PMID: 20816182
-
MacGregor EA et al. Guidelines for all healthcare professionals in the diagnosis and management of migraine. BASH Guidelines. 2019.
-
Silberstein SD et al. Evidence-based guideline: Pharmacologic treatment for episodic migraine prevention. Neurology. 2012;78(17):1337-1345. PMID: 22529202
Viva Points
"Migraine is a primary headache: unilateral, pulsating, moderate-severe, 4-72 hours, with nausea/vomiting/photo-phonophobia. Diagnose clinically with ICHD-3 criteria. Acute treatment: NSAID and/or triptan (take early). Prophylaxis if 4+ days/month: propranolol, amitriptyline, topiramate. CGRP inhibitors for refractory. Beware medication overuse headache."
Common Mistakes
- ❌ Not asking about red flags
- ❌ Prescribing triptans in cardiovascular disease
- ❌ Not warning about medication overuse headache
- ❌ Forgetting to consider prophylaxis for frequent attacks
- ❌ Missing hemiplegic migraine (contraindication to triptans)
Last Reviewed: 2026-01-01 | MedVellum Editorial Team