G43.9 ICD-10-CA code: Migraine, unspecified
G43.9 is the ICD-10-CA code for “Migraine, unspecified” in CIHI’s FY 2026–2027 release, in effect from Apr 1, 2026.
Official description
G43.9Migraine, unspecified
Short description: Migraine unspecified
ICD-10-CA · Canada · Also written G439
Index terms
Entries in CIHI’s alphabetical index that lead to G43.9. Searching the index by the condition the note names is how coders reach this code.
- Syndrome, migraine
- Migraine (idiopathic)
- Headache, migraine (type)
- Hemicrania, meaning migraine
Notes for G43.9
As CIHI prints them, with any note G43.9 takes from the headings above it.
Use additional code
Add a code for this detail when the note documents it.
- Use additional external cause code (Chapter XX) to identify drug, if drug-induced.From G43 Migraine
Excludes
Conditions classified elsewhere.
- Headache NOS (R51)From G43 Migraine
- Certain:• conditions originating in the perinatal period (P00-P96)• infectious and parasitic diseases (A00-B99)complications of pregnancy, childbirth and the puerperium (O00-O99)congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)endocrine, nutritional and metabolic diseases (E00-E90)injury, poisoning and certain other consequences of external causes (S00-T98)neoplasms (C00-D48)symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R99)From Chapter 6: Diseases of the nervous system (G00-G99)
Where G43.9 sits
- 1ChapterChapter 6: Diseases of the nervous system (G00-G99)
- 2Block G40-G47Episodic and paroxysmal disorders
- 3Category G43Migraine
- 4Valid code G43.9Migraine, unspecified
Source and release
- Data release
- ICD-10-CA · FY 2026–2027
- Effective date
- Apr 1, 2026
- Publisher
- CIHI
This page is built from the ICD-10-CA catalog that Vero Codes reads when it suggests codes: Canadian Institute for Health Information’s FY 2026–2027 release, imported from the publisher’s file and checked against it. The description, notes and structured data come from the same record.
Frequently asked questions
What does ICD-10-CA code G43.9 mean?
G43.9 is the ICD-10-CA code for “Migraine, unspecified” in CIHI’s ICD-10-CA FY 2026–2027 release.
Where is G43.9 in ICD-10-CA?
G43.9 sits under G43 Migraine, within G40-G47 Episodic and paroxysmal disorders, within Chapter 6: Diseases of the nervous system (G00-G99).
What coding notes apply to G43.9?
ICD-10-CA lists Use additional code, Excludes notes for G43.9, including those from the headings it sits under. They are listed on this page with where each one comes from.
Which ICD-10-CA release does this page use?
It uses CIHI’s FY 2026–2027 release, in effect from Apr 1, 2026 to Mar 31, 2027. It is a reference: confirm the code against the current list and the payer’s rules before you submit it.