Hemiplegic migraine is a rare type of migraine with aura that can cause temporary weakness or paralysis on one side of the body. It is a neurological condition that can also involve visual disturbances, numbness, tingling, difficulty speaking and severe headaches.
Unlike many other forms of migraine, hemiplegic migraine involves motor symptoms that can affect movement and coordination. These symptoms can sometimes resemble those of a stroke, making correct medical assessment particularly important.
This guide explains what hemiplegic migraine is, the symptoms to look out for, its possible causes, how it is diagnosed and the treatment options available.
Last reviewed: November 2026
What Is Hemiplegic Migraine?
Hemiplegic migraine is a rare subtype of migraine with aura characterised by temporary motor weakness affecting one side of the body.
The word hemiplegic relates to weakness or paralysis affecting one side of the body. Although the term suggests complete paralysis, many people experience varying degrees of muscle weakness rather than a complete inability to move.
The weakness may affect:
- One arm.
- One leg.
- The face.
- Several areas on the same side of the body.
Hemiplegic migraine is classified as a type of migraine with aura. This means that neurological symptoms can develop before or during the headache phase of an attack.
Some people experience visual disturbances, numbness, tingling or difficulties with speech alongside the weakness. In certain cases, the neurological symptoms may be more prominent than the headache itself.
Hemiplegic migraine is uncommon, and symptoms can vary considerably between individuals.
What Are the Symptoms of Hemiplegic Migraine?
The defining characteristic of hemiplegic migraine is temporary motor weakness affecting one side of the body. However, several other neurological and migraine-related symptoms can occur.
Motor weakness
Temporary weakness or paralysis can affect the face, arm or leg on one side of the body.
Some people experience difficulty lifting an arm, walking normally or coordinating their movements.
Visual disturbances
Visual symptoms can include:
- Flashing lights.
- Zigzag patterns.
- Sparkling or shimmering lights.
- Blind spots.
- Blurred vision.
- Temporary visual disturbances.
These symptoms are associated with migraine aura.
Sensory disturbances
Some people experience changes in sensation, including:
- Numbness.
- Tingling or pins and needles.
- Altered sensations in the face, arms or legs.
- Increased sensitivity to touch.
These sensations may develop gradually and can spread from one area of the body to another.
Speech and language difficulties
Hemiplegic migraine can affect communication and speech.
Possible symptoms include:
- Slurred speech.
- Difficulty finding the correct words.
- Trouble understanding spoken language.
- Difficulty expressing thoughts.
- Temporary speech impairment.
Other associated symptoms
Additional symptoms can include:
- Severe headache.
- Nausea and vomiting.
- Sensitivity to light (photophobia).
- Sensitivity to sound (phonophobia).
- Dizziness or vertigo.
- Confusion.
- Problems with balance and coordination.
- Extreme tiredness.
Not everyone experiences all these symptoms, and the pattern can differ between attacks.
What Causes Hemiplegic Migraine?
The precise mechanisms behind hemiplegic migraine are still being researched.
However, evidence suggests that changes in electrical and chemical activity within the brain play an important role.
Migraine aura is associated with a neurological process known as cortical spreading depression. This involves a wave of altered brain activity that moves across the cerebral cortex and can temporarily affect neurological function.
In hemiplegic migraine, this process is associated with motor symptoms, including weakness on one side of the body.
Genetic factors
Genetics can play an important role in some cases of hemiplegic migraine.
Researchers have identified several genes associated with familial hemiplegic migraine, including:
- CACNA1A.
- ATP1A2.
- SCN1A.
These genes are involved in the normal functioning of nerve cells and the movement of ions across cell membranes.
Changes in these genes can affect how nerve cells communicate and may increase susceptibility to migraine attacks.
However, not everyone with hemiplegic migraine has an identifiable genetic mutation.
Potential migraine triggers
Although triggers do not necessarily cause hemiplegic migraine itself, some people report that certain factors can contribute to migraine attacks.
Potential triggers may include:
- Emotional stress.
- Disrupted sleep.
- Hormonal changes.
- Skipping meals.
- Dehydration.
- Certain foods or drinks.
- Changes in routine.
- Environmental factors.
Identifying personal patterns may help people discuss possible triggers and management strategies with their healthcare professional.
What Are the Different Types of Hemiplegic Migraine?
There are two main classifications of hemiplegic migraine: familial hemiplegic migraine and sporadic hemiplegic migraine.
1. Familial Hemiplegic Migraine (FHM)
Familial hemiplegic migraine is diagnosed when a person experiences hemiplegic migraine and at least one first-degree or second-degree relative has also experienced attacks meeting the diagnostic criteria.
First-degree relatives include parents, siblings and children.
Second-degree relatives include grandparents, grandchildren, aunts, uncles, nieces, nephews and half-siblings.
Familial hemiplegic migraine can be associated with inherited genetic changes.
There are several recognised genetic subtypes, including:
- FHM1 – associated with the CACNA1A gene.
- FHM2 – associated with the ATP1A2 gene.
- FHM3 – associated with the SCN1A gene.
Not every person with familial hemiplegic migraine will have an identifiable mutation in these genes.
2. Sporadic Hemiplegic Migraine (SHM)
Sporadic hemiplegic migraine describes cases where the individual experiences hemiplegic migraine but has no first-degree or second-degree relative known to have experienced the same condition.
Some sporadic cases are associated with genetic changes that have occurred spontaneously, while others have no identifiable genetic explanation.
A lack of family history does not rule out hemiplegic migraine.
The symptoms of familial and sporadic hemiplegic migraine can be very similar.
How Is Hemiplegic Migraine Diagnosed?
Diagnosing hemiplegic migraine requires a detailed medical assessment because its symptoms can resemble other serious neurological conditions.
There is no single blood test or scan that independently confirms hemiplegic migraine.
Healthcare professionals generally consider:
- The person’s medical history.
- The nature and development of neurological symptoms.
- The duration of symptoms.
- Whether symptoms are reversible.
- The presence of associated migraine symptoms.
- Family history of similar attacks.
International diagnostic criteria
The International Classification of Headache Disorders, third edition (ICHD-3), provides recognised diagnostic criteria for hemiplegic migraine.
These include at least two attacks involving:
- Fully reversible motor weakness as part of the aura.
- Fully reversible visual, sensory and/or speech or language symptoms.
Additional criteria consider how symptoms develop, their duration, whether they affect one side of the body and their relationship to headache.
A healthcare professional must also consider and exclude other possible explanations.
Medical investigations
Depending on the symptoms and circumstances, investigations may include:
- Neurological examination.
- CT brain scan.
- MRI brain scan.
- Blood tests.
- Additional specialist investigations.
These investigations help healthcare professionals assess whether symptoms could be caused by stroke, transient ischaemic attack (TIA), epilepsy or another neurological condition.
Genetic testing may be considered in selected cases, particularly where there is a family history or other clinical reasons for investigation.
How Long Does Hemiplegic Migraine Last?
The duration of hemiplegic migraine symptoms varies.
Some people experience motor weakness lasting less than an hour, while others may experience symptoms lasting several hours or days.
Under the ICHD-3 diagnostic framework, motor symptoms generally last less than 72 hours, although they can persist for longer in some individuals.
Other symptoms, such as visual disturbances and sensory changes, may have different durations.
The headache phase and recovery period can also vary.
Some people experience tiredness, difficulty concentrating and a general feeling of being unwell after the main attack has ended.
This recovery period is often referred to as the migraine postdrome.
Any new, prolonged or unusual neurological symptoms require medical assessment rather than being automatically attributed to an existing migraine diagnosis.
What Treatments Are Available for Hemiplegic Migraine?
There is currently no cure for hemiplegic migraine, but healthcare professionals may recommend treatments to help manage attacks and reduce their frequency.
Treatment decisions can be more complicated than with other types of migraine because hemiplegic migraine is relatively rare and evidence for some treatments is limited.
A neurologist or headache specialist can help determine the most appropriate approach.
Acute migraine treatments
Acute treatments aim to manage symptoms during a migraine attack.
Depending on the individual’s medical history and diagnosis, options may include:
- Appropriate pain-relieving medication.
- Anti-sickness medication.
- Other specialist-prescribed migraine treatments.
Some migraine-specific medicines, including triptans, have historically been avoided in hemiplegic migraine because of concerns about their effects on blood vessels.
The evidence in this rare condition remains limited, and treatment decisions should be made by an appropriately qualified specialist. People should not start or change migraine medication without medical advice.
Preventative migraine treatments
Preventative treatments aim to reduce the frequency, duration or severity of migraine attacks.
Depending on the individual, a specialist may consider:
- Certain blood-pressure medicines.
- Some antidepressant medicines.
- Certain anti-seizure medicines.
- CGRP-targeting treatments.
- Other specialist preventative approaches.
Not every preventative treatment is suitable for every person, and availability through the NHS can vary.
Lifestyle and self-management
Some people find it useful to monitor their symptoms and maintain consistent daily routines.
Practical approaches may include:
- Maintaining regular sleep patterns.
- Eating meals at consistent times.
- Drinking sufficient fluids.
- Managing stress where possible.
- Recording symptoms and possible triggers.
- Discussing changes in attack frequency with a healthcare professional.
A migraine diary may help identify patterns and provide useful information during medical appointments.
Living With Hemiplegic Migraine
Living with hemiplegic migraine can be challenging because attacks may involve temporary physical weakness and other neurological symptoms.
The unpredictable nature of attacks can affect work, relationships, independence and everyday activities.
Some people may need additional support during or after an attack.
Keeping a migraine diary
A migraine diary can be a useful way to record:
- Date and time of attacks.
- Symptoms experienced.
- Duration of neurological symptoms.
- Headache severity.
- Medication taken.
- Possible triggers.
- Recovery time.
This information can help healthcare professionals understand how the condition affects an individual.
Preparing for medical appointments
People living with hemiplegic migraine may find it useful to keep a record of their diagnosis, treatment plan and previous investigations.
A written summary from a specialist can also help communicate an established diagnosis to other healthcare professionals.
However, a previous diagnosis must never be used to dismiss new or changing neurological symptoms.
Hemiplegic Migraine vs Stroke: What Is the Difference?
One of the most important things to understand about hemiplegic migraine is that its symptoms can closely resemble those of a stroke.
Both conditions can involve:
- Weakness on one side of the body.
- Facial weakness.
- Speech difficulties.
- Visual disturbances.
- Changes in sensation.
- Severe headache.
Migraine aura symptoms may develop gradually and progress from one symptom to another. Stroke symptoms often develop suddenly.
However, these differences are not reliable enough to distinguish the conditions without medical assessment.
Never assume that one-sided weakness, facial drooping or sudden speech difficulties are caused by migraine.
If you or someone else experiences sudden stroke-like symptoms, call 999 immediately, even if the symptoms begin to improve or disappear.
When Should You Seek Medical Help?
Immediate medical attention is essential when neurological symptoms occur for the first time or are different from a previously diagnosed migraine pattern.
Call 999 if you experience:
- Sudden weakness or paralysis on one side of the body.
- Facial drooping.
- Sudden difficulty speaking or understanding speech.
- Sudden loss of vision.
- A sudden, extremely severe headache.
- New confusion, seizures or reduced consciousness.
Do not drive yourself to A&E.
If you have an established diagnosis but experience a prolonged, worsening or unusual attack, seek urgent medical advice. NHS 111 can help direct you to appropriate care when emergency symptoms are absent.
Frequently Asked Questions About Hemiplegic Migraine
Is hemiplegic migraine a serious condition?
Hemiplegic migraine is a rare neurological condition that can cause significant temporary weakness and other neurological symptoms. Its symptoms can resemble a stroke, so prompt assessment is essential, particularly during a first or unusual attack.
Can hemiplegic migraine cause paralysis?
Yes. Hemiplegic migraine can cause temporary weakness or paralysis affecting one side of the body. The severity varies between individuals and attacks.
Can hemiplegic migraine affect speech?
Yes. Some people experience speech or language difficulties, including slurred speech and difficulty finding or understanding words.
Is hemiplegic migraine hereditary?
It can be. Familial hemiplegic migraine is associated with a family history of similar attacks and may involve inherited genetic changes. Sporadic hemiplegic migraine occurs without a known affected first-degree or second-degree relative.
Can you have hemiplegic migraine without a headache?
Hemiplegic migraine can involve prominent neurological symptoms, and headache severity can vary. The formal diagnostic classification requires the relevant migraine-with-aura criteria, so a specialist should assess attacks without headache.
How long can hemiplegic migraine symptoms last?
Motor weakness can last from minutes to hours or days. In some cases, it may persist for longer than 72 hours. New or prolonged symptoms should always be medically assessed.
Is there a cure for hemiplegic migraine?
There is currently no established cure. However, specialist treatment and preventative strategies may help some people manage their symptoms and reduce attacks.
Can hemiplegic migraine be mistaken for a stroke?
Yes. Both conditions can produce one-sided weakness, speech difficulties and visual disturbances. Suspected stroke symptoms must always be treated as a medical emergency.
Related Migraine Terms
You may also find these MKDART glossary entries useful:
- Migraine Aura
- Migraine With Aura
- Vestibular Migraine
- Familial Hemiplegic Migraine
- Sporadic Hemiplegic Migraine
- Motor Aura
- Photophobia
- Phonophobia
- Migraine Postdrome
- Status Migrainosus
Further Information and Trusted Resources
For further information about hemiplegic migraine, consult these established organisations and medical resources.
Information about hemiplegic migraine, symptoms, diagnosis and treatment.
Specialist information and factsheets about hemiplegic migraine.
International Headache Society – ICHD-3
The internationally recognised classification and diagnostic criteria for hemiplegic migraine.
General information about migraine symptoms, treatment and when to seek medical help.
Medical Information Disclaimer
This MKDART glossary entry is intended for educational and informational purposes only. It does not provide medical advice, diagnosis or treatment recommendations.
Information about migraine and neurological conditions should not be used as a substitute for assessment by a qualified healthcare professional.
Always seek urgent medical attention for new or sudden neurological symptoms, particularly one-sided weakness, facial drooping or speech difficulties.
About this glossary entry
- Website: MKDART – Migraine Knowledge, Diagnosis, Assessment & Relief Toolkit
- Author: MKDART Editorial Team
- Medical reviewer: Not yet independently medically reviewed
- Published: November 2026
- Last reviewed: November 2026