A hemiplegic migraine is a rare type of migraine that happens with one-sided muscle weakness. While this type of migraine isn’t a medical emergency, it can look and feel similar to a stroke. Contact emergency services right away if you notice any stroke-like symptoms. A healthcare provider can diagnose the difference and treat migraines.
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A hemiplegic migraine is a type of migraine headache that causes migraine symptoms and muscle weakness on one side of your body. Muscle weakness usually starts during the aura phase of a migraine, right before or during a headache attack. Muscle weakness may be accompanied by sensory, vision or speech changes.
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There are two types of hemiplegic migraines. Which type you have depends on what causes it:
A hemiplegic migraine is an alarming experience, but it isn’t an emergency. It can feel like an emergency because a migraine episode has similar symptoms to a stroke. A stroke is a medical emergency. Concerning symptoms of both conditions include one-sided muscle weakness, vision changes and difficulty speaking.
If you experience any stroke-like symptoms, call 911 (or your local emergency services number). If it’s a stroke, time is critical. Don’t try to diagnose the difference between a stroke and a hemiplegic migraine on your own — get emergency care right away.
While migraines are common; hemiplegic migraines aren’t. One study in Denmark found that hemiplegic migraines affect an estimated 1 in 10,000 people.
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Symptoms of a hemiplegic migraine include:
These symptoms usually match a regular migraine in the aura phase (right before or during a headache). But hemiplegic migraines can affect your muscles, speech and vision in ways other types of migraines don’t.
The symptoms can last for a few hours to days and rarely can last up to four weeks. The symptoms resolve completely in a majority of the cases.
A migraine headache causes severe, throbbing head pain. Head pain usually happens after or with one-sided muscle weakness. You’ll know you’re having a hemiplegic migraine after you lift both arms over your head. One of your arms will likely feel heavy and be more difficult to raise and keep upright than the other.
Overactive nerve cells may cause hemiplegic migraines. Specifically, a change in your nerves known as cortical spreading depression causes hemiplegic migraines.
Nerve cells carry an electric charge that helps ion molecules (charged particles) pass through it to help neurotransmitters send messages and communicate with different parts of your body. Cortical-spreading depression changes this electric charge (depolarization). It’s like a slow-moving wave that passes from one side of your brain to the other, disrupting the normal pattern of electric charge that your nerve cells carry. This leads to symptoms of a hemiplegic migraine.
A genetic change (mutation) affects how nerve cells function. The following gene variants have been identified in people experiencing hemiplegic migraine:
At this time, healthcare providers suspect not all subtypes have been identified.
Hemiplegic migraine triggers are similar to those for other types of migraines. Triggers vary from person to person but may include:
Some hemiplegic migraines start after a specific imaging test called a cerebral angiogram. This is a type of brain scan that identifies how well blood vessels in your brain function.
Most people who experience hemiplegic migraines get their first one during adolescence, between ages 12 and 17. As you get older, the number of migraines and the severity usually decreases.
Most hemiplegic migraine attacks get better (resolve) after a few days. However, in rare and severe cases, hemiplegic migraine symptoms can last for weeks. A migraine can take a toll on your mental and physical health. Symptoms can interrupt personal obligations, social commitments and your work or school.
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Severe complications are rare but may include:
A healthcare provider will diagnose a hemiplegic migraine after a physical exam and neurological exam. During these exams, your provider will ask you questions about your medical and family history. Let your provider know if you have biological relatives who experience migraines.
Tests are helpful to rule out conditions with similar symptoms. Your provider may offer the following tests:
A healthcare provider may recommend or prescribe medications for hemiplegic migraines, including:
Talk to your healthcare provider about the side effects of any medications they prescribe. They’ll tell you how often to take each dose.
You can’t prevent all hemiplegic migraines. Your provider may recommend taking preventive medications to reduce how often migraines affect you. But know that migraines are still possible if you take preventive medications. A provider can also prescribe medications to stop the migraine when it starts to reduce how long it lasts and the severity.
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Your provider can help you identify migraine triggers, which can reduce your risk.
You might feel panicked when symptoms of a hemiplegic migraine start, as they can be mistaken for a stroke if you haven’t experienced them before. The pain and weakness you feel can take you out of your routine and interrupt your life. The symptoms of a hemiplegic migraine go away after the migraine cycle ends. Treatment options are available to reduce how often these migraines happen.
Symptoms of a hemiplegic migraine can last from an hour to a few days. Symptoms usually go away within a day. The average number of hemiplegic migraine attacks per year is three. This number can range from person to person.
How many migraines you experience varies, from one each day to only a few during your lifetime. You may experience long, symptom-free periods between each migraine attack.
Many people report that migraine symptoms reduce in frequency with age. Usually after age 50, hemiplegic migraines transition into traditional migraines without muscle weakness. A healthcare provider can help you find treatment options to manage migraines throughout your life.
Contact a healthcare provider if you experience migraines with symptoms that affect your muscle strength.
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Call 911 or your local emergency services number right away if you notice symptoms of a stroke, including:
If you’re unsure whether you’re having a hemiplegic migraine or you’re having a stroke, contact emergency services. It’s better to be safe and under the care of a healthcare provider if you’re unsure or don’t have an official diagnosis.
When you experience a hemiplegic migraine, you’ll feel anxious and scared. Could it be a stroke? Do I need to call 911? Don’t hesitate to contact emergency services if you’re unsure. Your care team will diagnose what’s causing the symptoms. Then, they’ll help you manage your migraines and prevent how often they happen. Your healthcare providers will work with you to reduce the impact that hemiplegic migraines have on your life.
Last reviewed on 12/22/2023.
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