Is G43.C1 a billable ICD-10-CM code?

Yes. G43.C1 is a billable, specific ICD-10-CM code and is valid for submission on a claim.

Where does G43.C1 sit in the tabular list?

Diseases of the nervous system (G00-G99), in the block Episodic and paroxysmal disorders (G40-G47).

What cannot be coded together with G43.C1?

G43.C1 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above G43.C1 (G43) and apply to it just the same.

G43.C1

G43.C1 — Periodic headache syndromes in child or adult, intractable

Billable / specific codeICD-10-CM

G43.C1 is a billable, specific ICD-10-CM code for periodic headache syndromes in child or adult, intractable. It is valid for submission on a claim.

Inclusion terms

Alternative wordings a physician may use in the chart for this same code.

Periodic headache syndromes in child or adult, with refractory migraine

Excludes1 inherited from the categories above G43.C1

These are not written on G43.C1, but they bind it: a note on a category applies to every code beneath it. Billing G43.C1 with anything listed here is a denial.

Written on G43 — Migraine

lower half migraine (G44.00)

Excludes2 inherited from the categories above G43.C1

Also inherited, and the opposite of Excludes1: these conditions are not part of G43.C1, but a patient can have both, so you may code both.

Written on G43 — Migraine

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

Risk adjustment

G43.C1 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Medicare coverage

G43.C1 is named in 22 Medicare coverage policies — 22 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

A53057Billing and Coding: Home Health Occupational Therapy
A55530Billing and Coding: Peripheral Nerve Stimulation
A56273Billing and Coding: Chiropractic Services
A56551Billing and Coding: Visual Fields Testing

How G43.C1 is indexed

Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to G43.C1.

Headache›periodic syndromes in adults and children›intractable
Headache›periodic syndromes in adults and children›with refractory migraine

Code history

G43.C1 has not changed since FY2024 — no addition, revision or deletion across the three most recent ICD-10-CM releases.

Related codes at this level

Codes that share G43.C. If G43.C1 is not quite right, the correct code is usually one of these.

G43.C0Periodic headache syndromes in child or adult, not intractable

Questions about G43.C1

Is G43.C1 a billable ICD-10-CM code?: Yes. G43.C1 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does G43.C1 sit in the tabular list?: Diseases of the nervous system (G00-G99), in the block Episodic and paroxysmal disorders (G40-G47).
What cannot be coded together with G43.C1?: G43.C1 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above G43.C1 (G43) and apply to it just the same.