When Is a Migraine an Emergency?
he vast majority of migraine attacks, even severe ones, don't require a trip to the emergency room. A familiar migraine that isn't responding to treatment at home is unpleasant, but it's not a medical emergency. If someone is visiting the ED frequently for migraines, it usually means their day-to-day management needs to be looked at. However, certain headache features should never be ignored and need prompt evaluation to rule out something life-threatening.
Red Flag Symptoms That Require Emergency Assessment
Go to the ED immediately if a headache is accompanied by any of the following:
- Thunderclap onset peak severity within 60 seconds; possible subarachnoid haemorrhage
- New neurological symptoms one-sided weakness, speech difficulty, or confusion
- Fever and neck stiffness possible meningitis
- Headache after head trauma
- New headache in a patient over 50 with no migraine history
- Vision loss, jaw pain, or scalp tenderness possible giant cell arteritis
- Immunocompromised patient or active cancer
- Rapidly escalating headache unlike any previous attack
What Happens in the ED for a Severe Migraine?
The physician takes a history and performs a neurological exam. If the headache matches the patient’s known migraine pattern with no red flags, investigation may not be needed. When red flags are present, a CT scan, lumbar puncture, or blood work may follow.
Treatment then begins with IV or intramuscular (IM) medications, which bypass the gastric stasis that limits oral drug absorption during severe attacks. The goal is not complete pain relief it is reducing pain enough for the patient to go home, rest, and arrange specialist follow-up.
First-Line Emergency Medications for Migraine
Antiemetic Dopamine Antagonists (First-Line)
The best-evidenced first-line agents for acute migraine in the ED are antiemetic dopamine antagonists. They address both headache pain and nausea simultaneously.
- Prochlorperazine (10 mg IV) consistently outperforms opioids in trials; treats pain and nausea; may cause akathisia, preventable with diphenhydramine
- Metoclopramide (10-20 mg IV) works just as well, helps restore normal stomach function, and is less likely to cause akathisia.
- Chlorpromazine (12.5-25 mg IV) a solid option, though blood pressure needs to be kept an eye on throughout.
NSAIDs
- Ketorolac (15-30 mg IV or IM) good evidence behind it for migraine relief, commonly combined with an antiemetic for a stronger effect, and sidesteps the risks associated with opioids.
Triptans (If Not Previously Taken)
If no triptan has been taken at home, sumatriptan 6 mg subcutaneous injection is rapid and effective. Triptans are contraindicated in ischaemic heart disease, uncontrolled hypertension, or recent stroke.
Corticosteroids
- Dexamethasone (10 mg IV) not effective for the acute attack, but reduces 72-hour recurrence risk; routinely added before discharge
Opioids Why They Should Be Avoided
Despite being widely overused in the past, opioids are not recommended as a first-line treatment for migraines. The evidence shows they're no more effective than antiemetics, come with greater risks including sedation, dependency, and nausea and are linked to higher rates of medication overuse headache and repeat ED visits. Both the Canadian and American Headache Societies reserve them for situations where everything else has already failed.
IV Fluids and Supportive Care
IV fluids help correct dehydration and support the delivery of other medications. Beyond that, supportive care involves settling the patient in a quiet, darkened space, giving antiemetics for ongoing nausea, and keeping an eye out for akathisia a restless, uncomfortable side effect from dopamine antagonists as well as low blood pressure, which can occur with chlorpromazine.
Status Migrainosus
Status migrainosus is a migraine lasting more than 72 hours is a common reason for ED admission. First-line IV treatment applies, but refractory cases may require inpatient observation and escalation to IV valproate sodium, IV dihydroergotamine (DHE), or greater occipital nerve block.
After the ED Visit: Reducing Repeat Presentations
Repeated ED visits usually signal a gap in outpatient care. Before discharge, every patient should go home with:
- A bridging prescription - a short oral steroid course to lower the risk of the attack returning.
- An antiemetic to manage any nausea that continues at home.
- A clear follow-up plan - a referral to either a GP or a headache specialist.
- Guidance on medication overuse - frequent use of painkillers or triptans can paradoxically make headaches more frequent, and understanding this matters before walking out the door.
Patients attending the ED three or more times a year for migraine should be prioritised for specialist referral.
Conclusion
Emergency migraine treatment centres on fast-acting parenteral medications primarily prochlorperazine or metoclopramide, combined with ketorolac and dexamethasone. The ED excludes dangerous secondary causes and provides relief when home treatment fails. The best outcomes, however, depend on what follows: a bridging prescription, a follow-up plan, and improved outpatient management to prevent the next crisis.
