How should chronic migraine be managed, including preventive and acute treatment options?

Management of Chronic Migraine

For chronic migraine causing headache, initiate preventive therapy with topiramate, onabotulinumtoxinA, or CGRP monoclonal antibodies, as these are the only treatments with proven efficacy in randomized controlled trials specifically for chronic migraine. 1

Acute Treatment Strategy

Start with a stepwise approach for individual attacks:

First-line: NSAIDs (aspirin, ibuprofen, or diclofenac potassium) taken early in the headache phase 1

Second-line: Triptans when NSAIDs fail or for moderate-to-severe attacks 1, 2

• Consider combining triptans with fast-acting NSAIDs to prevent headache recurrence 1
• Use early in the attack for maximum effectiveness

Third-line: Gepants (CGRP receptor antagonists) or ditans (lasmiditan) 1

• Note: Lasmiditan causes driving impairment for at least 8 hours after use 1

Adjunct therapy: Prokinetic antiemetics (domperidone or metoclopramide) for nausea/vomiting 1, 2

Critical pitfall: Warn patients that frequent acute medication use (>10 days/month for triptans, gepants, or combination analgesics) risks medication overuse headache (MOH), which can perpetuate chronic migraine 1

Avoid completely: Oral ergot alkaloids, opioids, and barbiturates due to poor efficacy, toxicity, and dependency risk 1

Preventive Treatment Strategy

Indications for preventive therapy in chronic migraine:

• Headaches on ≥15 days per month with migraine features on ≥8 days
• Quality of life impairment despite optimized acute therapy
• Overuse of acute medications 1

Evidence-Based Preventive Options

Topiramate is the first-choice preventive medication due to lower cost and proven efficacy in multiple RCTs for chronic migraine 1, 3

• This is the ONLY traditional oral preventive with robust chronic migraine-specific evidence

OnabotulinumtoxinA (Botox) is FDA-approved specifically for chronic migraine prophylaxis 3

• Assess efficacy after 6-9 months 1
• Regulatory restrictions often require failure of 2-3 other preventives first 1

CGRP monoclonal antibodies (erenumab, fremanezumab, galcanezumab) have proven efficacy in chronic migraine 1, 4

• Particularly effective in patients who failed at least two other preventives 1
• Assess efficacy after 3-6 months 1
• Generally reserved for refractory cases due to cost and regulatory restrictions 1

Atogepant (oral CGRP receptor antagonist) shows efficacy in both episodic and chronic migraine 4, 5

Important Evidence Gap

Beta-blockers, candesartan, and amitriptyline lack robust RCT data for chronic migraine specifically, though they are commonly used in clinical practice based on episodic migraine evidence 1. The 2021 Nature Reviews Neurology guideline explicitly states no robust data from randomized controlled trials support their use in chronic migraine 1.

Treatment Timeline Expectations

• Oral preventives: Assess efficacy after 2-3 months 1
• CGRP antibodies: Assess after 3-6 months 1
• OnabotulinumtoxinA: Assess after 6-9 months 1
• Counsel patients that preventive efficacy is rarely immediate; discourage early abandonment 1

Medication Overuse Headache Management

If MOH is present (acute medication use ≥10 days/month for triptans/gepants or ≥15 days/month for simple analgesics):

1. Abrupt withdrawal of overused medication (preferred method) 1
   • Exception: Taper opioids gradually 1
2. Educate patient that symptoms will worsen before improving 1
3. Start or continue preventive therapy during withdrawal 1
4. This can be managed in primary care unless addictive drugs are involved 1

Specialist Referral Indications

Refer to neurology/headache specialist when:

• Chronic migraine diagnosis is established 1
• Two or more preventive medications have failed
• MOH involves opioids or other addictive substances 1
• Diagnostic uncertainty exists

Comorbidity Considerations

Screen for and address:

• Depression and anxiety (consider amitriptyline if present) 1
• Obesity (topiramate preferred due to weight loss effect) 1
• Sleep disturbances (amitriptyline may help) 1
• Cardiovascular risk factors (avoid triptans; use gepants or lasmiditan instead) 4, 6

Non-Pharmacologic Adjuncts

Consider adding:

• Cognitive behavioral therapy
• Biofeedback
• Relaxation techniques
• Physical therapy or aerobic exercise 4, 7

These behavioral interventions show significant symptom improvement, especially in refractory cases 7.

Critical Clinical Pitfalls

1. Underdiagnosis: Only 20% of patients meeting chronic migraine criteria receive the correct diagnosis 3
2. Inadequate trial duration: Abandoning preventives before adequate trial period
3. Ignoring MOH: Preventives will fail if medication overuse continues
4. Using episodic migraine evidence for chronic migraine: Most traditional preventives lack chronic migraine-specific RCT data 1
5. Acetaminophen monotherapy: Not effective for migraine 2