Migraine: When to See a Doctor, What Causes It, and How to Treat It

When Should You Worry About a Migraine?

Most migraine attacks are disabling but not life-threatening. The critical task is separating a primary headache disorder from a secondary headache caused by a dangerous underlying condition. The American Headache Society uses the mnemonic SNOOP4 to flag high-risk features, and any single one of them justifies same-day or emergency evaluation [1].

The SNOOP4 Red Flags

The SNOOP4 criteria cover the features most likely to indicate a secondary cause:

• S (Systemic symptoms or disease): fever, unexplained weight loss, known cancer, HIV, or immunosuppression alongside the headache.
• N (Neurological signs): new confusion, weakness on one side, diplopia, dysarthria, or ataxia that outlasts the headache itself.
• O (Onset sudden): the thunderclap headache, reaching maximum intensity within 60 seconds. A single thunderclap presentation has a subarachnoid hemorrhage (SAH) rate of roughly 11 to 12% in ED studies [2].
• O (Older age at onset): new headache disorder appearing after age 50 raises concern for giant cell arteritis, intracranial mass, or cerebrovascular disease.
• P (Positional change): headache that worsens dramatically when lying down may suggest raised intracranial pressure; headache that worsens when standing may indicate low cerebrospinal-fluid pressure.
• P (Papilledema): swelling of the optic disc on fundoscopy is a hard sign of elevated intracranial pressure.
• P (Progressive pattern): a headache that has been gradually worsening over weeks or months without relief.
• P (Prior headache change): a person with a known migraine history whose attacks have changed substantially in character, frequency, or severity.

The Thunderclap Headache

A thunderclap headache deserves special attention. Call emergency services or go directly to an emergency department. Do not wait to see if it resolves. Subarachnoid hemorrhage, cerebral venous sinus thrombosis, and reversible cerebral vasoconstriction syndrome can all present this way [2]. A normal CT scan does not exclude SAH within the first 6 hours; lumbar puncture or CT angiography may still be required.

When a Scheduled Appointment Is Enough

If your headaches lack all SNOOP4 features but occur four or more days per month, or if over-the-counter analgesics are being used on ten or more days per month, a scheduled visit within one to two weeks is appropriate. Frequent analgesic use on 10+ days per month meets the International Classification of Headache Disorders, 3rd edition (ICHD-3) threshold for medication-overuse headache, a condition that perpetuates the very pain it is taken to treat [3].

What Causes Migraine?

Migraine is a primary neurological disorder driven by abnormal cortical excitability and trigeminovascular activation, not simply a vascular event. The pathophysiology is well-characterized across several overlapping mechanisms [4].

Cortical Spreading Depression

The aura phase of migraine corresponds to cortical spreading depression (CSD): a slow wave of neuronal depolarization moving across the cortex at 3 to 5 mm per minute [4]. CSD activates trigeminal afferents around cortical blood vessels, releasing calcitonin gene-related peptide (CGRP) and other nociceptive mediators that produce the pain phase.

The CGRP Pathway

CGRP is the most therapeutically important mediator identified in migraine biology. Plasma CGRP levels rise during spontaneous attacks and fall after effective triptan treatment [5]. Intravenous CGRP infusion reliably triggers migraine in susceptible individuals [5]. This mechanism underpins the entire class of gepants (oral CGRP-receptor antagonists) and anti-CGRP monoclonal antibodies approved since 2018.

Genetic and Hormonal Contributors

Migraine heritability is estimated at 40 to 65% from twin studies [6]. First-degree relatives of migraine sufferers have a roughly three-fold elevated lifetime risk [6]. Estrogen withdrawal is a major trigger: the sharp estrogen drop in the late luteal phase explains why migraine prevalence is three times higher in women than men after puberty, converging again after menopause [7]. Other well-documented triggers include sleep disruption, skipped meals, dehydration, alcohol (particularly red wine), stress, and bright or flickering light.

Sensitization and Chronification

With repeated attacks, central sensitization of the trigeminal nucleus caudalis lowers the threshold for subsequent attacks. Episodic migraine (fewer than 15 headache days per month) progresses to chronic migraine (15 or more headache days per month, at least 8 of which meet migraine criteria) in approximately 2.5% of episodic sufferers each year [8]. Obesity, depression, sleep apnea, and medication overuse are the strongest modifiable risk factors for chronification [8].

How Is Migraine Diagnosed?

Migraine diagnosis is clinical. No blood test, imaging study, or biomarker is required for a straightforward presentation. The ICHD-3 criteria, published by the International Headache Society, provide the diagnostic standard [3].

ICHD-3 Criteria for Migraine Without Aura

A diagnosis requires at least five attacks, each lasting 4 to 72 hours untreated, with at least two of these four pain features: unilateral location, pulsating quality, moderate or severe intensity, or aggravation by routine physical activity. The attack must also include nausea or vomiting, or photophobia and phonophobia [3].

ICHD-3 Criteria for Migraine With Aura

At least two attacks are required. The aura consists of at least one fully reversible visual, sensory, speech, motor, brainstem, or retinal symptom [3]. Aura symptoms spread gradually over at least five minutes, last between five and 60 minutes, and at least one is unilateral. The headache follows or accompanies the aura within 60 minutes.

Validated Screening Tools

The ID-Migraine screener asks three questions: photophobia, nausea, and disability. Two of three positive responses yield a sensitivity of 81% and specificity of 75% for migraine diagnosis in primary care [9]. The MIDAS (Migraine Disability Assessment) questionnaire scores disability across the preceding 90 days and helps guide treatment intensity decisions.

When Imaging Is Indicated

Neuroimaging is not needed for a typical migraine history. The American Academy of Neurology (AAN) guideline states that routine CT or MRI is not indicated for patients with recurrent headaches who have normal neurological exams and no red-flag features [10]. Imaging is appropriate for new neurological signs, first or worst headache, progressive pattern, or failure of two or more preventive drug classes.

Acute Migraine Treatment: Stopping an Attack in Progress

The goal of acute treatment is freedom from pain at two hours, sustained to 24 hours, without recurrence. Stratified care, matching drug potency to attack severity, outperforms step-care approaches in reducing disability days [11].

Triptans: The Established Standard

Triptans are serotonin 5-HT1B/1D agonists. Sumatriptan, the first in class, remains the most studied. Oral sumatriptan 50 to 100 mg achieves 2-hour pain freedom in approximately 30 to 40% of patients versus 10 to 15% for placebo [11]. The subcutaneous formulation (6 mg) acts faster, with 2-hour pain freedom rates near 57% [11]. Seven triptans are available in the United States; if the first fails, switching to a different triptan or route is reasonable before abandoning the class.

Triptans are contraindicated in patients with ischemic heart disease, uncontrolled hypertension, or stroke history due to their vasoconstrictive mechanism. They should not be combined with ergotamine derivatives.

Gepants: CGRP-Receptor Antagonists

Ubrogepant (Ubrelvy) and rimegepant (Nurtec ODT) are oral CGRP-receptor antagonists approved for acute treatment [12]. They carry no cardiovascular contraindication and do not cause the vasoconstriction seen with triptans. ACHIEVE-I (N=1,327) showed ubrogepant 100 mg achieved 2-hour pain freedom in 21.2% versus 11.8% for placebo (P<0.001) [12]. Rimegepant is unique in holding dual approval for both acute and preventive use.

Lasmiditan: A Non-Vasoconstricting Option

Lasmiditan (Reyvow) is a selective 5-HT1F agonist with no vasoconstrictive activity, approved for patients who cannot take triptans [13]. SAMURAI (N=1,856) showed lasmiditan 200 mg produced 2-hour pain freedom in 32.2% versus 15.3% for placebo [13]. Dizziness and sedation are common; patients must not drive for at least eight hours after a dose.

NSAIDs and Combination Analgesics

For mild-to-moderate attacks, naproxen sodium 500 to 550 mg or ibuprofen 400 to 600 mg may suffice. The combination of aspirin 900 mg plus metoclopramide 10 mg is recommended by the European Federation of Neurological Societies and achieves 2-hour pain relief comparable to sumatriptan 50 mg in direct-comparison trials [14]. Metoclopramide also addresses the nausea and gastric stasis that impair oral drug absorption during attacks.

Preventive Migraine Treatment: Reducing Attack Frequency

Prevention is warranted when attacks occur four or more days per month, when acute medications are used on ten or more days per month, when attacks are severely disabling, or when acute medication is contraindicated [15].

First-Line Oral Preventives

The AAN evidence-based guideline assigns Level A evidence to topiramate and valproate (anticonvulsants) and to propranolol and timolol (beta-blockers) [15]. Topiramate 50 to 100 mg/day reduces monthly migraine days by approximately 2.3 compared to placebo over 26 weeks (P<0.001) [15]. Valproate is highly effective but teratogenic and must be avoided in women of childbearing potential. Amitriptyline 10 to 75 mg at bedtime is widely used with Level B evidence.

Anti-CGRP Monoclonal Antibodies

Four anti-CGRP or anti-CGRP-receptor monoclonal antibodies are approved for migraine prevention in the United States: erenumab (Aimovig), fremanezumab (Ajovy), galcanezumab (Emgality), and eptinezumab (Vyepti) [16]. These are given monthly or quarterly by subcutaneous or intravenous injection.

The STRIVE trial (erenumab, N=955) showed 70 mg monthly reduced mean monthly migraine days by 3.2 versus 1.8 for placebo at 6 months [16]. The HALO-CM trial (fremanezumab, N=1,130) in chronic migraine showed quarterly dosing reduced monthly headache days by 4.6 versus 2.5 for placebo [17].

Onset of benefit can occur within the first month, substantially faster than oral preventives, which typically require 8 to 12 weeks to assess efficacy.

OnabotulinumtoxinA (Botox) for Chronic Migraine

OnabotulinumtoxinA 155 to 195 units injected across 31 sites every 12 weeks is FDA-approved specifically for chronic migraine (not episodic). The PREEMPT program (N=1,384 pooled) demonstrated a reduction of 8.4 mean headache days per 28 days versus 6.6 for placebo after 24 weeks [18]. Patients who have failed two oral preventives are good candidates.

Behavioral and Lifestyle Prevention

Regular sleep schedules, consistent meal timing, aerobic exercise three to five days per week, and cognitive behavioral therapy each carry supporting evidence [19]. A 2017 Cochrane review found that aerobic exercise is comparable to topiramate in reducing migraine frequency in adults who complete a 12-week program, though the confidence interval was wide [19]. Biofeedback and relaxation training hold Level A evidence in the AAN guideline for migraine prevention.

Migraine in Special Populations

Migraine With Aura and Cardiovascular Risk

Women who have migraine with aura and use combined oral contraceptives face a compounded ischemic stroke risk. The absolute risk remains low but the combination is generally avoided; progestin-only or non-hormonal contraception is preferred [7]. The WHO Medical Eligibility Criteria for Contraceptive Use categorizes combined hormonal contraceptives as Category 4 (unacceptable risk) for women with migraine with aura [7].

Migraine During Pregnancy

Triptans, topiramate, and valproate carry fetal risk concerns. Acetaminophen at the lowest effective dose for the shortest duration is the first-line acute option during pregnancy [20]. Magnesium sulfate IV is used for severe refractory attacks and has a reasonable safety profile in pregnancy. The anti-CGRP monoclonal antibodies have no pregnancy safety data and should be discontinued when pregnancy is confirmed.

Pediatric Migraine

Migraine affects approximately 10% of school-age children [21]. Attacks are often shorter (2 to 72 hours) and more frequently bilateral in children than in adults. Ibuprofen 10 mg/kg and sumatriptan nasal spray (10 to 20 mg) have the strongest pediatric acute-treatment evidence [21]. Topiramate and amitriptyline are the most studied pediatric preventives, though a large NIH-funded trial (CHAMP, N=328) found neither superior to placebo on the primary endpoint of 50% responder rate after 24 weeks [22].

Migraine and Medication-Overuse Headache

Using any acute headache medication on ten or more days per month for three or more months can produce medication-overuse headache (MOH), formerly called rebound headache. Triptans and combination analgesics carry a lower overuse threshold (ten days) than simple analgesics such as ibuprofen or acetaminophen (fifteen days) [3].

MOH affects an estimated 1 to 2% of the global population and is the third most common headache disorder worldwide [3]. Treatment requires withdrawal of the overused medication, which produces a transient worsening for 7 to 10 days before improvement. Bridging with naproxen sodium or a short course of oral prednisone may reduce withdrawal severity, though prednisone evidence is mixed. Preventive medication should be started concurrently with withdrawal.

Tracking Migraines: The Headache Diary

A prospective headache diary completed for at least four to eight weeks gives a clinician the data needed to count migraine days accurately, identify triggers, and measure medication use. Apps such as Migraine Buddy and the American Migraine Foundation's diary tool record date, duration, pain intensity, associated symptoms, medications taken, and potential triggers [23]. Bringing diary data to the first specialist appointment substantially reduces the diagnostic workup time.

The diary also clarifies whether headaches meet the threshold for preventive treatment and whether medication overuse is contributing to frequency.

What to Expect at a Headache Specialist Appointment

A neurologist or headache specialist will take a detailed headache history covering onset, location, quality, duration, associated symptoms, triggers, prior treatments, and family history. A neurological examination assessing cranial nerves, coordination, gait, and cognitive function follows. The ICHD-3 criteria are applied to assign a diagnosis or diagnoses (many patients have both migraine and tension-type headache).

The American Migraine Foundation states: "The goal of migraine treatment is not just to treat the pain, but to restore the patient to normal function as quickly and completely as possible, and to prevent future attacks." Achieving that goal typically requires trying at least one acute strategy and one preventive strategy before the combination that works for any individual patient is found.

Expect to leave with a written treatment plan, a rescue medication for severe attacks, a preventive medication if frequency or disability justifies it, and a follow-up appointment in 4 to 8 weeks.