What Is a Hemiplegic Migraine?
Hemiplegic migraine is a rare and serious type of migraine headache. Many of its symptoms mimic those common to stroke. For example, muscle weakness can be so extreme that it causes a temporary paralysis on one side of your body, which doctors call hemiplegia.
Hemiplegic Migraine Symptoms
You may have early symptoms before the actual headache pain. Early symptoms called aurasmay cause:
- Short-term trouble with muscle control and sensation
- Severe, throbbing pain, often on one side of your head
- A pins-and-needles feeling, often moving from your hand up your arm
- Numbness on one side of your body, which can include your arm, leg, and half of your face
- Weakness or paralysis on one side of your body
- Loss of balance and coordination
- Dizziness or vertigo
- Nausea and vomiting
Other aura symptoms may include:
- Seeing zigzag lines, double vision, or blind spots
- Extreme sensitivity to light, sound, and smell
- Language difficulties, such as mixing words or trouble remembering a word
- Slurred speech
- Confusion
- Drowsiness or loss of consciousness
Auras usually come on gradually over a half-hour, and then can last for hours and then slowly resolve. They can be more severe and last longer than with other types of migraine.
Hemiplegic Migraine vs. Stroke
You have a terrible headache. How do you know the cause? The short answer is: You don’t. Some of the symptoms of a migraine can be very much like those of a stroke.
If you think there's even the slightest chance you're having a stroke, call 911 right away. Early treatment can limit the damage to your brain and possibly save your life.
If you're over 40 and have never had a migraine, assume your pain is something more serious, especially if you notice stroke symptoms like paralysis or slurred speech. People who get migraines typically have it most of their lives. It's rare to have your first symptoms when you're older.
The stroke-like symptoms of hemiplegic migraine can range from worrisome to disabling. Unlike stroke symptoms, they come on slowly and build and then may completely go away. Muscle problems usually go away within 24 hours, but they may last a few days.
There's not a predictable pattern with this type of migraine. Usually, pain follows the paralysis, but it might come before, or you might not get a headache at all. You may hurt a lot and feel only a little weak; then the next attack might bring severe paralysis without much pain.
It's uncommon, but over time, some people can have long-lasting trouble with movement and coordination.
Hemiplegic migraine symptoms often start when you're a child or teen. Sometimes, they'll disappear when you're an adult.
Hemiplegic Migraines Causes
So far, researchers have found four genes linked with hemiplegic migraine:
- CACNA1A
- ATP1A2
- SCN1A
- PRRT2
Defects, or mutations, in any of these can make your body less able to make a certain protein. Without it, nerve cells have trouble sending out or taking in signals that go between them. One of these chemical messengers, or neurotransmitters, is serotonin.
A child of a parent with hemiplegic migraines will have a 50% chance of getting them as well.
Tests to Diagnose Hemiplegic Migraines
A CT scan or an MRI of your head can show signs of a stroke and so rule it out as a cause of your symptoms. Tests of your heart and the blood vessels in your neck can rule out blood clots as a cause of your symptoms.
If you have a family member with similar symptoms, your doctor may want to do genetic testing. Familial hemiplegic migraine (FHM) means it runs in your family, and you could pass it on to your children. People who don't have problems with those four genes have sporadic hemiplegic migraine (SHM).
Hemiplegic Migraine Treatment
Doctors don’t always agree on the best way to treat hemiplegic migraines.
Your doctor might prescribe drugs to prevent hemiplegic migraines, to stop them once they've started, or to relieve your symptoms. It’s a good idea to discuss these options with your doctor.
There is controversy over whether some drugs that are used to treat other types of migraines should be used for hemiplegic migraines. There is some evidence that triptans, beta-blockers, and ergotamine derivatives may lead to ischemia (when a part of your body isn’t getting enough blood) in patients with hemiplegic migraine. But more research is needed to be sure.
CGRP inhibitors are a new class of preventive medicine for treating most common migraines, but early studies suggest they would not work for hemiplegic migraines.