Is G44.01 a billable ICD-10-CM code?

No. G44.01 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does G44.01 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 G44.01?

G44.01 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 G44.01 (G44) and apply to it just the same.

G44.01

G44.01 — Episodic cluster headache

Non-billable headerICD-10-CM

G44.01 is a non-billable header ICD-10-CM code for episodic cluster headache. It cannot be billed on its own: choose one of the more specific child codes below.

Excludes1 inherited from the categories above G44.01

These are not written on G44.01, but they bind it: a note on a category applies to every code beneath it. Billing G44.01 with anything listed here is a denial.

Written on G44 — Other headache syndromes

headache NOS (R51.9)

Excludes2 inherited from the categories above G44.01

Also inherited, and the opposite of Excludes1: these conditions are not part of G44.01, but a patient can have both, so you may code both.

Written on G44 — Other headache syndromes

atypical facial pain (G50.1)
headache due to lumbar puncture (G97.1)
migraines (G43.-)
trigeminal neuralgia (G50.0)

Risk adjustment

G44.01 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.

Code history

G44.01 has not changed since FY2024 — no addition, revision or deletion across the three most recent ICD-10-CM releases.

Code to one of these instead G44.01

2 child codes. Green means billable.

Related codes at this level

Codes that share G44.0. If G44.01 is not quite right, the correct code is usually one of these.

Questions about G44.01

Is G44.01 a billable ICD-10-CM code?: No. G44.01 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does G44.01 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 G44.01?: G44.01 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 G44.01 (G44) and apply to it just the same.