G43.91 – Migraine, unspecified, intractable

ICD-10-CM 2027 diagnosis code · Episodic and paroxysmal disorders

Non-billable header

ICD-10-CM code G43.91

Code: G43.91 (claims format: G4391)
Description: Migraine, unspecified, intractable
Billable: No – use a more specific code below
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 6. Diseases of the nervous system (G00-G99)
Block: G40-G47 Episodic and paroxysmal disorders
Parent codes: G43 › G43.9

Billable codes under G43.91

G43.91 is a header code and cannot be used on claims. Choose the most specific code:

Notes for G43.91

Applicable to:

Migraine, unspecified, with refractory migraine

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

G43 – Migraine

Excludes1 (not coded here):

lower half migraine (G44.00)

Excludes2 (not included here):

headache NOS (R51.9)
headache syndromes (G44.-)

Use additional code:

code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5)

Notes:

the following terms are to be considered equivalent to intractable: pharmacoresistant (pharmacologically resistant), treatment resistant, refractory (medically) and poorly controlled

Related codes in G43.9

G43.90 – Migraine, unspecified, not intractableHeader

Frequently asked questions

What is ICD-10 code G43.91?

G43.91 is the ICD-10-CM code for migraine, unspecified, intractable, in the block G40-G47 (Episodic and paroxysmal disorders).

Is G43.91 a billable code?

No. G43.91 is a header code with more specific child codes; report one of the billable codes listed above.

What category does G43.91 belong to?

It belongs to category G43 – Migraine.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.