Alphabetic Index FY2027

G44.0

Cluster headaches and other trigeminal autonomic cephalgias (TAC)

FY2027Chapter 6: Diseases of the nervous system/G40–G47 Episodic and paroxysmal disorders

Non-billable headerNot valid on its own. Use one of the more specific codes under it.

G44.0 is a non-billable ICD-10-CM code header for cluster headaches and other trigeminal autonomic cephalgias (TAC). Report a more specific code from it instead. It is part of the FY2027 code set, effective October 1, 2026. The more specific codes under it are G44.00 Cluster headache syndrome, unspecified; G44.01 Episodic cluster headache; G44.02 Chronic cluster headache; G44.03 Episodic paroxysmal hemicrania and 3 more. Its coding notes include 1 Excludes1 entry and 12 Excludes2 entries.

Excludes1

Not coded here. The listed conditions generally should not be reported together.

Inherited from G44 Other headache syndromes

Excludes2

Not included here. Both codes may be reported if the patient has both conditions.

Inherited from G44 Other headache syndromes
  • atypical facial pain (G50.1)
  • headache due to lumbar puncture (G97.1)
  • migraines (G43.-)
  • trigeminal neuralgia (G50.0)
Also from chapter/block level (8 notes)
Inherited from Chapter 6 Diseases of the nervous system
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

More specific codes under G44.0 7