2021 ICD-10-CM Diagnosis Code G44.001

Cluster headache syndrome, unspecified, intractable

    2016 2017 2018 2019 2020 2021 Billable/Specific Code
  • G44.001 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
  • The 2021 edition of ICD-10-CM G44.001 became effective on October 1, 2020.
  • This is the American ICD-10-CM version of G44.001 - other international versions of ICD-10 G44.001 may differ.
The following code(s) above G44.001 contain annotation back-references
Annotation Back-References
In this context, annotation back-references refer to codes that contain:
  • Applicable To annotations, or
  • Code Also annotations, or
  • Code First annotations, or
  • Excludes1 annotations, or
  • Excludes2 annotations, or
  • Includes annotations, or
  • Note annotations, or
  • Use Additional annotations
that may be applicable to G44.001:
  • G00-G99
    2021 ICD-10-CM Range G00-G99

    Diseases of the nervous system

    Type 2 Excludes
    • 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)
    Diseases of the nervous system
  • G44
    ICD-10-CM Diagnosis Code G44

    Other headache syndromes

      2016 2017 2018 2019 2020 2021 Non-Billable/Non-Specific Code
    Type 1 Excludes
    Type 2 Excludes
    • atypical facial pain (G50.1)
    • headache due to lumbar puncture (G97.1)
    • migraines (G43.-)
    • trigeminal neuralgia (G50.0)
    Other headache syndromes
  • G44.00
    ICD-10-CM Diagnosis Code G44.00

    Cluster headache syndrome, unspecified

      2016 2017 2018 2019 2020 2021 Non-Billable/Non-Specific Code
    Applicable To
    • Ciliary neuralgia
    • Cluster headache NOS
    • Histamine cephalgia
    • Lower half migraine
    • Migrainous neuralgia
    Cluster headache syndrome, unspecified
Approximate Synonyms
  • Cluster headache, intractable
  • Intractable cluster headache
ICD-10-CM G44.001 is grouped within Diagnostic Related Group(s) (MS-DRG v38.0):
  • 102 Headaches with mcc
  • 103 Headaches without mcc

Convert G44.001 to ICD-9-CM

Code History
  • 2016 (effective 10/1/2015): New code (first year of non-draft ICD-10-CM)
  • 2017 (effective 10/1/2016): No change
  • 2018 (effective 10/1/2017): No change
  • 2019 (effective 10/1/2018): No change
  • 2020 (effective 10/1/2019): No change
  • 2021 (effective 10/1/2020): No change

Diagnosis Index entries containing back-references to G44.001:
  • Cephalgia, cephalalgia - see also Headache
    • histamine G44.009
      ICD-10-CM Diagnosis Code G44.009

      Cluster headache syndrome, unspecified, not intractable

        2016 2017 2018 2019 2020 2021 Billable/Specific Code
      Applicable To
      • Cluster headache syndrome NOS
      • intractable G44.001
  • Headache R51.9
    ICD-10-CM Diagnosis Code R51.9

    Headache, unspecified

      2021 - New Code Billable/Specific Code
    Applicable To
    • Facial pain NOS
    • cluster G44.009
      ICD-10-CM Diagnosis Code G44.009

      Cluster headache syndrome, unspecified, not intractable

        2016 2017 2018 2019 2020 2021 Billable/Specific Code
      Applicable To
      • Cluster headache syndrome NOS
      • intractable G44.001
    • histamine G44.009
      ICD-10-CM Diagnosis Code G44.009

      Cluster headache syndrome, unspecified, not intractable

        2016 2017 2018 2019 2020 2021 Billable/Specific Code
      Applicable To
      • Cluster headache syndrome NOS
      • intractable G44.001
  • Neuralgia, neuralgic (acute) M79.2
    ICD-10-CM Diagnosis Code M79.2

    Neuralgia and neuritis, unspecified

      2016 2017 2018 2019 2020 2021 Billable/Specific Code
    Type 1 Excludes
    • ciliary G44.009
      ICD-10-CM Diagnosis Code G44.009

      Cluster headache syndrome, unspecified, not intractable

        2016 2017 2018 2019 2020 2021 Billable/Specific Code
      Applicable To
      • Cluster headache syndrome NOS
      • intractable G44.001
    • migrainous G44.009
      ICD-10-CM Diagnosis Code G44.009

      Cluster headache syndrome, unspecified, not intractable

        2016 2017 2018 2019 2020 2021 Billable/Specific Code
      Applicable To
      • Cluster headache syndrome NOS
      • intractable G44.001
  • Syndrome - see also Disease
    • cluster headache G44.009
      ICD-10-CM Diagnosis Code G44.009

      Cluster headache syndrome, unspecified, not intractable

        2016 2017 2018 2019 2020 2021 Billable/Specific Code
      Applicable To
      • Cluster headache syndrome NOS
      • intractable G44.001

ICD-10-CM Codes Adjacent To G44.001
G43.9 Migraine, unspecified
G43.90 Migraine, unspecified, not intractable
G43.901 …… with status migrainosus
G43.909 …… without status migrainosus
G43.91 Migraine, unspecified, intractable
G43.911 …… with status migrainosus
G43.919 …… without status migrainosus
G44 Other headache syndromes
G44.0 Cluster headaches and other trigeminal autonomic cephalgias (TAC)
G44.00 Cluster headache syndrome, unspecified
G44.001 …… intractable
G44.009 …… not intractable
G44.01 Episodic cluster headache
G44.011 …… intractable
G44.019 …… not intractable
G44.02 Chronic cluster headache
G44.021 …… intractable
G44.029 …… not intractable
G44.03 Episodic paroxysmal hemicrania
G44.031 …… intractable
G44.039 …… not intractable

Reimbursement claims with a date of service on or after October 1, 2015 require the use of ICD-10-CM codes.