Exercise-Induced Migraine: Diagnosis and Management
Diagnosis
Exercise-induced migraine should be diagnosed when recurrent migraine attacks (lasting 4-72 hours with moderate-to-severe pulsating headache, photophobia, phonophobia, and nausea) are consistently triggered by physical exertion, after excluding secondary causes through careful history and physical examination. 1
Key Diagnostic Features
- Headache characteristics: Unilateral or bilateral pulsating pain of moderate-to-severe intensity, aggravated by routine physical activity, lasting 4-72 hours 1
- Associated symptoms: Photophobia, phonophobia, nausea, and/or vomiting 1
- Temporal relationship: Onset during or shortly after exercise (often within minutes in the locker room or immediately post-exertion) 2
- Aura symptoms: May include visual disturbances (fortification spectra) or sensory symptoms in approximately one-third of cases 1, 2
Critical Differential Diagnoses to Exclude
Approximately 10% of exercise-induced headaches have a serious organic origin, making exclusion of secondary causes mandatory. 3, 2
- Life-threatening conditions requiring immediate evaluation: Subarachnoid hemorrhage (explosive onset), mass lesions, posterior fossa abnormalities, increased intracranial pressure 4
- Exercise-induced anaphylaxis: Distinguished by pruritus, cutaneous warmth/erythema, punctate urticaria progressing to potential vascular collapse—requires immediate epinephrine and is NOT migraine 1
- Cardiac-induced headache: Consider if significant cardiovascular risk factors present; exercise stress test appropriate 4
- Primary exertional headache: Typically shorter duration (<48 hours), lacks migraine-associated symptoms 3
Diagnostic Workup
- Detailed history: Document timing relative to exercise, food ingestion, medication use (especially NSAIDs/aspirin), environmental factors, warm-up adequacy, and family history of migraine 1
- Physical examination: Exclude secondary causes; neuroimaging only when secondary headache disorder suspected 1
- Headache diary: Essential for tracking attack frequency, triggers, duration, and treatment response 1
Management
Non-Pharmacological Interventions (First-Line)
The hallmark of treatment is proper warm-up before exercise, minimization of environmental risks, adequate sleep hygiene, and optimal nutrition and hydration. 3
- Exercise modification: Reduce intensity or duration; ensure adequate warm-up period 3, 5
- Avoid post-prandial exercise: Do not exercise for 4-6 hours after eating if food-dependent pattern identified 1
- Environmental optimization: Address heat, altitude, dehydration as potential triggers 3
- Regular moderate aerobic exercise: Paradoxically, regular exercise may have prophylactic effects by altering migraine threshold through increased beta-endorphins, endocannabinoids, and brain-derived neurotrophic factor 6, 5
Acute Pharmacological Treatment
For acute attacks, NSAIDs are first-line for mild-to-moderate attacks; triptans are recommended for moderate-to-severe attacks or NSAID failure. 7
- First-line: Ibuprofen 400-800 mg, diclofenac potassium, or aspirin 7
- Second-line: Triptans (sumatriptan 50-100 mg); maximum 200 mg in 24 hours 7
- Combination therapy: Triptan PLUS NSAID (e.g., sumatriptan 50-100 mg + naproxen 500 mg) for superior efficacy 8
- Timing: Administer early in headache phase for maximum effectiveness 7
Prophylactic Therapy
Prophylactic therapy should be initiated for patients with ≥2 migraine attacks per month with disability lasting ≥3 days per month, or when acute medications are used more than twice weekly. 9, 7
First-Line Prophylactic Options
- Beta-blockers: Propranolol 80-240 mg/day or timolol 20-30 mg/day 9, 7, 8
- Topiramate: 50-100 mg daily (additional benefit: weight loss) 7, 8
- Amitriptyline: 30-150 mg/day (particularly beneficial with comorbid depression or sleep disturbances) 9, 7, 8
- Divalproex sodium: 500-1500 mg/day 9
Implementation Strategy
- Start low, titrate slowly: Begin with low dose and increase gradually until clinical benefit or side effects limit further increases 9
- Adequate trial period: Allow 2-3 months before determining efficacy 9, 8
- Monitor with headache calendars: Track frequency, severity, duration, disability, and medication use 9, 7
Critical Pitfalls to Avoid
Medication Overuse Headache (MOH)
Strictly limit acute medications to ≤2 days per week: triptans to <10 days/month and NSAIDs to <15 days/month to prevent MOH. 7, 8
- MOH creates vicious cycle: Increased acute medication use paradoxically worsens headache frequency, potentially leading to daily headaches 8
- Management: Exclude MOH before escalating treatment; withdraw overused medication (preferably abruptly) 8
Exercise-Induced Anaphylaxis Misdiagnosis
Never confuse exercise-induced migraine with exercise-induced anaphylaxis—the latter requires immediate epinephrine and can be life-threatening. 1
- Anaphylaxis red flags: Pruritus, cutaneous warmth, urticaria, respiratory symptoms, vascular collapse 1
- Anaphylaxis management: Discontinue exercise immediately at first symptom; administer epinephrine; patients must carry injectable epinephrine during all exercise 1
Inadequate Secondary Cause Exclusion
Failure to exclude serious secondary causes (subarachnoid hemorrhage, mass lesions, posterior fossa abnormalities) in the 10% of cases with organic etiology can be catastrophic. 3, 2, 4
Prophylactic Antihistamines
Prophylactic H1/H2 antihistamines are generally NOT effective for exercise-induced migraine (though they may help selected patients with exercise-induced anaphylaxis). 1
Special Considerations
- Comorbidities: Identify and treat depression, sleep disorders, obesity, and cardiovascular risk factors; select prophylactic medications that address both conditions (e.g., amitriptyline for depression, topiramate for obesity) 7, 8
- Adjuvant therapies: Consider cognitive behavioral therapy, biofeedback, relaxation therapy, or acupuncture as complementary interventions 8
- Exercise companion: Patients should exercise with a companion aware of their condition and capable of providing emergency assistance 1