ICD-10-CM 2027
ICD-10 code for cluster headache syndrome
From the official ICD-10-CM alphabetic index entry “Syndrome › cluster headache”. Page updated September 29, 2026.
About coding cluster headache syndrome
The ICD-10-CM code for cluster headache syndrome is G44.009 (Cluster headache syndrome, unspecified, not intractable). The official index lists 2 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on G44.009.
Within G44.00 (cluster headache syndrome, unspecified), G44.009 is specifically for cluster headache syndrome, unspecified, not intractable. Related codes cover intractable (G44.001).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 102 (Headaches with MCC, relative weight 1.1201) and DRG 103 (Headaches without MCC, relative weight 0.822), in MDC 01 (Diseases and Disorders of the Nervous System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific cluster headache syndrome codes (official index)
Common questions about cluster headache syndrome ICD-10 codes
What is the ICD-10 code for cluster headache syndrome?
- G44.009 — Cluster headache syndrome, unspecified, not intractable. More specific codes apply when the documentation supports them: G44.001, G44.009.
What is the ICD-10 code for intractable cluster headache syndrome?
- G44.001 — Cluster headache syndrome, unspecified, intractable.
Is G44.009 billable?
- Yes. G44.009 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can G44.009 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict G44.009 as a principal diagnosis.
Is G44.009 a CC or MCC?
- No. G44.009 is neither a CC nor an MCC under MS-DRG v44.0.