ICD-10 Code G43.409 – Hemiplegic migraine, not intractable, without status migrainosus (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code G43.409 – Hemiplegic migraine, not intractable, without status migrainosus
What it is
This code identifies hemiplegic migraine, a migraine subtype that includes temporary one-sided weakness along with migraine symptoms. “Not intractable” means the headache is not documented as resistant to treatment, and “without status migrainosus” means it is not a prolonged migraine attack.
Clinical signs
Typical features include migraine headache with reversible motor weakness on one side of the body. Aura, sensory changes, or speech disturbance may occur; clinical features vary, so refer to documentation.
When to use this code
Use G43.409 when the provider documents hemiplegic migraine and does not describe it as intractable or status migrainosus. It is appropriate for outpatient, emergency, or follow-up encounters when the diagnosis is established and supported in the record. Check documentation if the note does not clearly specify the migraine type.
Do not use for
Do not use this code for ordinary migraine, migraine with aura alone, or hemiplegia from stroke or other neurologic disease. If the record says intractable migraine or status migrainosus, choose the documented code instead.
Coding tip
Code only when the record clearly links the weakness to hemiplegic migraine and confirms the nonintractable, non-status migrainosus wording.