Migraine is a complex neurological disorder characterized by recurrent episodes of moderate to severe headache, typically accompanied by nausea, vomiting, and sensitivity to light and sound. It is one of the most common and disabling neurological conditions worldwide, affecting approximately 1 in 7 people and ranked among the top causes of years lived with disability globally. It is three times more prevalent in women than men.
While migraine is a clinical diagnosis, brain MRI is an important tool for excluding serious secondary causes of headache — particularly when headache patterns are new, changing, or accompanied by neurological symptoms. Conditions that must be excluded include brain aneurysm (especially the sudden "thunderclap" headache of subarachnoid hemorrhage), brain tumors, subdural hematoma, and stroke. Migraineurs — particularly women with migraine with aura — frequently show small white matter lesions on MRI that are generally benign but warrant acknowledgment.
Causes
Neurological and vascular mechanisms
Migraines result from complex neurological events involving cortical spreading depression — a slow-moving wave of neuronal depolarization and suppression that propagates across the cortex, underlying the aura phenomenon — along with activation of the trigeminovascular pain pathway. Trigeminal nerve activation triggers the release of inflammatory neuropeptides, particularly calcitonin gene-related peptide (CGRP), which causes vasodilation and neurogenic inflammation around meningeal vessels, producing the characteristic throbbing head pain. CGRP has become the primary pharmacological target of the newest and most effective migraine treatments. Genetic factors play a significant role — first-degree relatives of migraineurs have a 2–4 fold increased risk.
Common triggers
Triggers precipitate attacks in susceptible individuals but do not cause the underlying migraine predisposition. Common triggers include hormonal changes (particularly estrogen fluctuations around menstruation — the most powerful trigger in women), stress and stress let-down, sleep disruption (both too much and too little), skipping meals, certain foods and beverages (alcohol especially red wine, caffeine, aged cheeses, processed meats with nitrates), bright or flickering lights, strong smells, and barometric pressure changes. Identifying personal triggers through a headache diary is a valuable management strategy, though over-restriction should be avoided.
Symptoms
A migraine attack often progresses through four distinct phases:
- Prodrome (hours to days before): Mood changes, food cravings, neck stiffness, increased yawning, and fatigue — symptoms that experienced migraineurs learn to recognize as attack warnings.
- Aura (present in approximately 30% of patients): Reversible focal neurological symptoms developing gradually over 5–20 minutes and lasting under 60 minutes. Visual aura is most common — flickering lights (scintillating scotoma), zigzag lines (fortification spectra), or expanding blind spots. Sensory, speech, and motor aura are less common. Aura symptoms that are prolonged, persist after the headache, or occur for the first time in an older patient warrant MRI evaluation to exclude stroke or vascular malformation.
- Headache phase (4–72 hours): Throbbing, pulsating pain — typically unilateral but may be bilateral — worsened by routine physical activity. Accompanied by nausea, vomiting, photophobia, and phonophobia. Severe attacks are profoundly disabling.
- Postdrome (hours after headache): Fatigue, cognitive fog ("migraine hangover"), difficulty concentrating, and general malaise — often underappreciated as part of the migraine syndrome.
Diagnosis
Migraine is a clinical diagnosis based on characteristic history and headache features as defined by the International Headache Society (ICHD-3) criteria — no biomarker or imaging test is required for a straightforward diagnosis. A thorough history, headache diary review, and neurological examination are the foundation of diagnosis.
MRI of the brain is performed to exclude secondary causes of headache when red flag features are present — a new or different headache, the "worst headache of one's life" (raising concern for subarachnoid hemorrhage), headache awakening from sleep, progressive worsening, new neurological symptoms, headache in an older patient, or headache with fever or neck stiffness. MRI is also appropriate when atypical aura features raise concern for stroke or vascular pathology. Small, punctate white matter lesions are a well-recognized incidental finding in migraineurs — particularly women with migraine with aura — and are generally considered benign, not associated with increased stroke or dementia risk in isolation.
Classification
Migraines are classified by the International Headache Society based on clinical features:
- Migraine without aura: Most common form — characteristic headache without preceding focal neurological symptoms. Diagnosis requires at least five attacks meeting ICHD-3 criteria.
- Migraine with aura: Preceded by reversible focal neurological symptoms, most commonly visual. Associated with a modestly increased risk of ischemic stroke, particularly in women who smoke or use estrogen-containing contraceptives.
- Chronic migraine: Headache occurring 15 or more days per month for more than 3 months, with migraine features on at least 8 days — a significantly disabling condition warranting aggressive preventive therapy.
- Hemiplegic migraine: Rare form with aura including reversible motor weakness — may be familial (FHM) with identified gene mutations. Must be distinguished from stroke in the acute setting.
Treatments
Migraine management encompasses acute (abortive) therapy to stop an attack and preventive therapy to reduce attack frequency and severity. A combination of pharmacological and non-pharmacological approaches is most effective, individualized to the patient's attack frequency, severity, and comorbidities.
Acute treatment:
NSAIDs (ibuprofen, naproxen, aspirin) and acetaminophen are effective for mild to moderate attacks. Triptans — selective serotonin 5-HT1B/1D receptor agonists (sumatriptan, rizatriptan, eletriptan) — are the gold standard acute treatment for moderate to severe migraine, working by constricting meningeal vessels and blocking CGRP release. Gepants (ubrogepant, rimegepant) — oral CGRP receptor antagonists — are highly effective acute treatments with the advantage of being safe in patients with cardiovascular contraindications to triptans. Lasmiditan (a selective 5-HT1F agonist) is an additional option. Antiemetics (metoclopramide, prochlorperazine) treat nausea and have independent analgesic properties. Early treatment at attack onset consistently produces better outcomes than delayed treatment.
Preventive treatment:
Preventive therapy is indicated when attacks are frequent (4 or more per month), severely disabling, or when acute medications are overused. Traditional options include beta-blockers (propranolol, metoprolol), tricyclic antidepressants (amitriptyline), and anticonvulsants (topiramate, valproate). CGRP-targeted monoclonal antibodies (erenumab, fremanezumab, galcanezumab, eptinezumab) have transformed migraine prevention — monthly or quarterly injections provide 50% or greater reduction in monthly migraine days in approximately half of patients, with excellent tolerability and minimal systemic side effects. Botulinum toxin (Botox) injections every 12 weeks are FDA-approved specifically for chronic migraine prevention and highly effective in this population.
Non-pharmacological approaches:
Cognitive behavioral therapy (CBT), biofeedback, and relaxation training have strong evidence for migraine prevention. Regular sleep schedule, consistent meal timing, aerobic exercise, stress management, and adequate hydration all reduce attack frequency. Neuromodulation devices (Cefaly transcutaneous supraorbital stimulation, gammaCore vagus nerve stimulator) are FDA-cleared non-pharmacological options for both prevention and acute treatment.
Get an MRI to Confirm Your Diagnosis
Before surgical planning or starting treatment, a clear MRI diagnosis ensures the right path forward. First Look MRI offers self-pay Brain MRI scans — no doctor's order or insurance required — at our locations in Georgia, Texas, and Colorado.