India
Neurology · 4 min read

Sporadic hemiplegic migraine

Learn about Sporadic hemiplegic migraine, its reported features, relevant specialists, and questions to discuss at a medical consultation.

Also known as: Non-familial hemiplegic migraine; SHM

Compiled from public sources
Text selected and arranged from MedlinePlus (US National Library of Medicine) genetics. It describes the condition as those sources do; it has not been rewritten for India.
01 Oct 2026
Not medically reviewed
No registered doctor has reviewed this page. Use it to decide who to see and what to ask — not to diagnose or treat.
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This is not medical advice. If symptoms are severe, sudden or getting worse, call 112 (or 108 for an ambulance) or go to the nearest emergency department.

The sources compiled here do not cover: diagnosis, treatment, prevention, prevalence. Ask the treating doctor about these.

What it is, symptoms and effects

From: MedlinePlus Genetics, National Library of Medicine

Sporadic hemiplegic migraine is a rare form of migraine headache. Migraines typically cause intense, throbbing pain in one area of the head. Some people with migraines also experience nausea, vomiting, and sensitivity to light and sound. These recurrent headaches typically begin in childhood or adolescence and can be triggered by certain foods, emotional stress, and minor head trauma. Each headache may last from a few hours to a few days.

In sporadic hemiplegic migraine and some other types of migraine, a pattern of neurological symptoms called an aura occurs before onset of the headache. An aura commonly includes temporary visual changes such as blind spots (scotomas), flashing lights, zig-zagging lines, and double vision. In people with sporadic hemiplegic migraine, auras are also characterized by temporary numbness or weakness, often affecting one side of the body (hemiparesis). Additional features of an aura can include difficulty with speech, confusion, and drowsiness. An aura typically develops gradually over a few minutes and lasts about an hour.

Some people with sporadic hemiplegic migraine experience unusually severe migraine episodes. These episodes can include fever, prolonged weakness, seizures, and coma. Although most people with sporadic hemiplegic migraine recover completely between episodes, neurological symptoms such as memory loss and problems with attention can last for weeks or months. Some affected individuals develop mild but permanent difficulty coordinating movements (ataxia), which may worsen with time, and rapid, involuntary eye movements called nystagmus. Mild to severe intellectual disability has been reported in some people with sporadic hemiplegic migraine.

Inheritance

From: MedlinePlus Genetics, National Library of Medicine

Autosomal dominant; Not inherited

Understanding terms used in the source

These definitions explain medical words used above. A definition is not evidence that another condition is present, and it does not predict how a symptom will develop. Ask the clinician which terms apply to the actual examination or test result.

Severe intellectual disability
Severe intellectual disability (ID) is defined as a type of ID characterized by severely sub-average adaptive functioning and intellectual functioning, with an intelligence quotient (IQ) the range of 20-34.
Intellectual disability
The term intellectual disability or intellectual developmental disorder is used to describe significantly sub-average intellectual and adaptive functioning based on clinical assessment and as measured by individually administered, appropriately normed, standardized and validated tests of intellectual functioning and adaptive behavior, with onset during the developmental period from infancy through adolescence.
Triggered by
A trigger is defined as an external factor that leads to the manifestation of a sign or symptom in a person with a susceptibility to developing that manifestation.
Hemiparesis
Loss of strength in the arm, leg, and sometimes face on one side of the body. Hemiplegia refers to a complete loss of strength, whereas hemiparesis refers to an incomplete loss of strength.
Nystagmus
Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms.

When it may begin

From: MedlinePlus Genetics, National Library of Medicine

These recurrent headaches typically begin in childhood or adolescence and can be triggered by certain foods, emotional stress, and minor head trauma. In sporadic hemiplegic migraine and some other types of migraine, a pattern of neurological symptoms called an aura occurs before onset of the headache.

Inheritance in the source

From: MedlinePlus Genetics, National Library of Medicine

Autosomal dominant; Not inherited

Which doctor should you see?

The suggested department for discussing Sporadic hemiplegic migraine is Neurology, with a neurologist as the relevant type of clinician. General physician / Family Medicine; paediatrician for children. Referral depends on symptoms.

Additional services that may be relevant, depending on the findings, include: Clinical Genetics.

This is an editorial referral starting point. The appropriate clinic depends on the person’s age, symptoms, previous diagnosis and local services. The first clinician can decide whether another specialty or a team is needed; a department label does not confirm the diagnosis.

How to prepare for an assessment

Bring a short timeline of the main symptoms: when they first appeared, whether they are constant or episodic, what seems to change them, and how they affect daily activities. Include previous reports, discharge summaries, current medicines and supplements, allergies, and any relevant family history. A dated record is more useful than trying to match every feature in an online article.

Ask the clinician what is already established and what remains uncertain. If a test is suggested, ask what question it answers, what its limitations are and how the result would change the next step. The information here is not an instruction to arrange every possible test. In children, bring growth, developmental and school information if it is relevant to the concern.

  • Which nervous-system findings help explain the symptoms?
  • Would an assessment of walking, communication or daily function be helpful?
  • Are rehabilitation or other specialist services relevant?

Treatment discussions and follow-up

The material gathered for this draft does not provide a complete condition-specific treatment pathway for Sporadic hemiplegic migraine. That gap does not mean that treatment is unavailable. A clinician needs to establish the diagnosis and review current guidance before recommending medicines, procedures, rehabilitation or other support.

Before leaving the appointment, clarify the next review date, who will communicate results, and whom to contact if the situation changes. Discuss difficulties with sleep, work, school, mobility, eating or emotional wellbeing when these are relevant. Practical support may require coordination between the treating clinician and other services.

The collected references do not establish a complete prevention or long-term outlook section for this entry. Missing information should not be interpreted as proof that prevention is impossible or that a particular outcome is inevitable. Ask what is known for the exact subtype, stage and personal circumstances, and which uncertainties remain.

When to seek emergency help

Severe breathing difficulty, collapse, new stroke-like symptoms, a seizure that is prolonged or repeated without recovery, uncontrolled major bleeding, or an immediate risk of self-harm require emergency help. In India, call 112 or reach the nearest emergency department. This is a general, non-exhaustive warning list; it is not a condition-specific triage tool.

Find a doctor for Sporadic hemiplegic migraine

This condition is usually assessed by a neurologist. Every profile shows the doctor’s registration and what has been checked.

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Sources

Source: MedlinePlus, National Library of Medicine. Orphadata Science: Free access data from Orphanet. © INSERM 1999; July 2026 data, CC BY 4.0. This product uses the Human Phenotype Ontology (hp/releases/2026-09-01). Only sources listed for this article apply. Source material has been selected and arranged; HPO definitions are reproduced without alteration. No source organisation endorses this compilation. Köhler S et al. The Human Phenotype Ontology project: linking molecular biology and disease through phenotype data. Nucleic Acids Research 2014;42(D1):D966–D974. doi:10.1093/nar/gkt1026.

General information, not advice about your situation. Errors can be reported through the corrections process. Reference TDI-C-2235.