Familial Hemiplegic Migraine: Causes, Symptoms, and Treatment
Medically reviewed by Harsha Moole, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Familial Hemiplegic Migraine?
A neurologist, a doctor who treats brain and nerve conditions, usually leads care for familial hemiplegic migraine. Children may see a pediatric neurologist. A medical geneticist, a doctor for inherited conditions, can help with testing. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is familial hemiplegic migraine?
Familial hemiplegic migraine is a form of migraine headache that runs in families. Migraines usually cause intense, throbbing pain in one area of the head. Nausea, vomiting, and extreme sensitivity to light and sound are common. In this type, a pattern of nerve symptoms called an aura comes before the headache. Hemiplegic means weakness on one side of the body.
These headaches usually start in childhood or the teen years. Like other forms of migraine, it affects females more often than males.
Symptoms
An attack has an aura phase and a headache phase. Signs can include:
- Weakness on one side of the body during the aura, from mild to severe.
- Vision changes, such as blind spots, flashing lights, zigzag lines, and double vision.
- Numbness or a prickly feeling.
- Trouble with speech, confusion, and drowsiness.
- A throbbing headache with nausea, vomiting, and extreme sensitivity to light and sound.
An aura usually lasts about an hour, but it can take up to a week to go away fully. Attacks can range from about one a day to fewer than five in a lifetime, and they usually become less frequent with age. Most people recover fully between episodes.
Some attacks are severe. They can bring fever, seizures, long-lasting weakness, coma, and, rarely, death. Memory loss and problems with attention can last for weeks or months. About 20 percent develop ataxia. This is mild, lasting trouble with coordination.
Causes and who gets it
Changes in the CACNA1A, ATP1A2, SCN1A, and PRRT2 genes can cause familial hemiplegic migraine. The first three genes help nerve cells move charged particles, called ions. Some people have the condition but no change in these genes.
The condition is inherited in an autosomal dominant pattern, which means one changed copy of the gene is enough to cause it. An affected parent has a 50% risk of passing the changed gene to a child in each pregnancy. Some people who inherit a changed gene never develop the condition.
Attacks can be set off by triggers. These include certain foods, certain odors, bright light, too little or too much sleep, physical exertion, stress, or minor head trauma.
How doctors diagnose it
Doctors use typical symptoms, a detailed history, an exam, and specialized tests. A person generally has two attacks of migraine with aura. The weakness on one side must fully go away and come with another aura symptom. For the familial form, a first- or second-degree relative must also have the disorder.
Brain imaging is usually normal. Genetic testing can confirm the diagnosis in some people. Only specialized labs offer this test. Stroke, multiple sclerosis, brain tumors, and epilepsy can cause similar signs, so doctors rule these out.
Treatment
Treatment is aimed at the symptoms each person has. It may need a team of specialists. There are no standardized treatment protocols or guidelines. Treatment has two parts: care during an attack, and daily preventive medicine to reduce how often attacks happen.
Pain relievers can ease the headache. No acute treatment has been proven to reduce the strength and length of the aura. Most people should avoid triptans and ergotamines, two kinds of migraine medicine. They can narrow blood vessels and raise the risk of stroke.
Preventive medicines used for regular migraines can be tried. These include tricyclic antidepressants, beta blockers, calcium channel blockers, and anti-seizure medicines. A severe attack, especially with high fever, reduced alertness, or seizures, may need a hospital stay. Genetic counseling is advised for patients and their families.
When to see a doctor
See a doctor if you or your child has migraine headaches with weakness on one side of the body, vision changes, or trouble speaking. Stroke can cause signs similar to those of hemiplegic migraine. Call 911 or go to the emergency room if sudden weakness, trouble speaking, or a sudden change in vision is new or you are not sure what is causing it. Also call 911 for a seizure, a high fever, or if the person is confused or hard to wake.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. Such a doctor can review symptoms and triggers, help plan specialist visits, and follow general health between attacks.
Common questions
Can a hemiplegic migraine look like a stroke?
Yes, stroke can cause signs similar to those of hemiplegic migraine. Doctors use symptoms, history, and specialized tests to tell the causes apart.
Does familial hemiplegic migraine run in families?
Yes, it is inherited in an autosomal dominant pattern, so one changed copy of the gene is enough to cause it. In most cases, an affected person has one affected parent.
Is there a standard treatment for familial hemiplegic migraine?
No, there are no standardized treatment protocols or guidelines. Treatment is aimed at the symptoms each person has.
How long does the weakness last?
The weakness is temporary, and an aura usually lasts about an hour. In severe attacks, weakness and speech trouble can last for several days or weeks but usually fully resolve.
Sources
- MedlinePlus Genetics - Familial hemiplegic migraine
- National Organization for Rare Disorders - Hemiplegic Migraine
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
