What is the definition and approach to managing menstrual migraines?

Menstrual Migraine: Definition and Management Approach

Definition

Menstrual migraine is defined as migraine without aura occurring exclusively or predominantly during the perimenstrual window (day 1 ± 2 of menstruation), with two distinct subtypes recognized. 1, 2

• Pure menstrual migraine: Attacks occur only during the perimenstrual window (2 days before through 3 days after menstruation onset) in at least 2 out of 3 menstrual cycles, with no attacks at other times—affects approximately 8% of women with migraine 2, 3, 4

• Menstrually-related migraine: Attacks occur during the perimenstrual window but also at other times during the menstrual cycle—affects a larger percentage of female migraineurs (6-7%) 3, 4

• The pathophysiology centers on estrogen withdrawal as the primary trigger, making menstruation a uniquely important and self-evident trigger factor in migraine management 1, 4, 5

• These attacks are typically more severe, longer-lasting, and more resistant to standard acute treatment compared to non-menstrual migraines 3

Acute Treatment Approach

Start with NSAIDs as first-line therapy for mild-to-moderate attacks, escalating to triptans when NSAIDs provide inadequate relief. 1, 2

First-Line: NSAIDs

• Use acetylsalicylic acid, ibuprofen (400-800mg every 6 hours), or diclofenac potassium as initial therapy 1, 2
• Naproxen sodium 275-550mg every 2-6 hours is also effective 2
• Administer early when headache is still mild for maximum effectiveness 1, 2

Second-Line: Triptans

• Rizatriptan 10mg has the strongest evidence for acute menstrual migraine treatment, with pain-free responses of 33-73% at 2 hours and sustained pain relief of 63% between 2-24 hours 3
• Sumatriptan 50-100mg and rizatriptan show similar efficacy (61-63% for 2-hour pain freedom) 2, 3
• Eletriptan 40mg is effective for acute migraine treatment with 2-hour response rates of 57-70% 6
• Take triptans early when headache is mild, but never during aura phase as they are ineffective at that time 1, 2
• Combine triptans with fast-acting NSAIDs (like naproxen) to prevent headache recurrence 1, 2

Medications to Avoid

• Avoid opioids and barbiturates due to dependency risk, rebound headaches, and poor efficacy 2
• Oral ergot alkaloids should be avoided due to poor efficacy and potential toxicity 2

Perimenstrual Prophylaxis (Short-Term Prevention)

When acute treatment alone is insufficient, use perimenstrual prophylaxis with long-acting NSAIDs or triptans for 5 days, beginning 2 days before expected menstruation. 2

Long-Acting Triptans (Preferred)

• Frovatriptan 2.5mg twice daily has the strongest evidence from four randomized controlled trials 2, 3, 7
• Naratriptan 1mg twice daily is supported by two studies 2, 3, 7
• Zolmitriptan three times daily is supported by one trial 3, 7

Long-Acting NSAIDs

• Naproxen sodium started 2 days before expected menstruation and continued for 5 days 2, 3, 8
• This approach is recommended by the American Academy of Neurology 2

Hormonal Options

• Transcutaneous estradiol 1.5mg daily (gel or patch) applied perimenstrually has grade B evidence for pure menstrual migraine 2, 5
• Continuous combined hormonal contraceptives (CHCs) with no placebo pills or only 2 days of placebo can benefit women with pure menstrual migraine without aura 2, 4
• CHCs are absolutely contraindicated in women with migraine with aura due to increased stroke risk 9, 4

Daily Preventive Therapy

For women with frequent migraines throughout the month (not just menstrually-related), use standard daily preventive medications. 2, 9

First-Line Daily Preventives

• Beta-blockers: Propranolol 80-160mg daily or metoprolol 50-100mg twice daily 2, 9
• Candesartan 16-32mg daily if beta-blockers are contraindicated 9

Second-Line Daily Preventives

• Amitriptyline 10-100mg at night 9
• Topiramate 50-100mg daily (but contraindicated in pregnancy and has least effect on oral contraceptives at doses <200mg/day) 2, 9, 3

Absolute Contraindication

• Sodium valproate is absolutely contraindicated in women of childbearing potential 1, 9

Monitoring and Follow-Up

Use headache calendars to track attack frequency, severity, medication use, and menstruation timing for at least 3 complete cycles to confirm diagnosis and guide treatment decisions. 1, 2, 7

• Evaluate treatment response within 2-3 months after initiation or change in treatment 2, 9
• Monitor for medication overuse (>10 days/month of acute medication use) to prevent medication overuse headache 1, 2
• If one preventive fails, try another drug class as failure of one does not predict failure of others 2
• Limit triptan use and educate patients about rebound headache risk 2

Critical Pitfalls to Avoid

• Never prescribe combined hormonal contraceptives to women with migraine with aura—this significantly increases stroke risk 9, 4
• Do not use triptans during the aura phase; wait until headache begins 1, 2
• Avoid delaying triptan administration once headache starts—early treatment when pain is mild yields best results 1, 7
• Do not overlook medication overuse as a cause of treatment failure—discourage use of acute medications >10 days per month 1, 2
• Remember that many antiepileptic preventive medications can reduce oral contraceptive efficacy through enzyme induction 3