2026 ICD-10-CM Diagnosis Code G90.9Disorder of the autonomic nervous system, unspecified

ICD-10-CM Codes›G00–G99›G89-G99›G90

ICD-10-CM G90.9
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

G90.9 is a billable ICD-10-CM diagnosis code for disorder of the autonomic nervous system, unspecified. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other nervous system disorders (neither hereditary nor degenerative).

Code Identity

ICD-10-CM Code
G90.9
Billable Status
Yes — Valid for Submission
Code Describes
Disorder of the autonomic nervous system, unspecified
Short Description
Disorder of the autonomic nervous system, unspecified
Same as the full description in the CMS dataset.
Parent Code
G90
Disorders of autonomic nervous system

Code Classification

ChapterG00–G99Diseases of the nervous system
SectionG89-G99Other disorders of the nervous system
CategoryG90Disorders of autonomic nervous system
This CodeG90.9Disorder of the autonomic nervous system, unspecified

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Amyotrophic lateral sclerosis plus syndrome
  • Amyotrophic lateral sclerosis with autonomic dysfunction
  • Anhidrosis
  • Autoimmune disorder of autonomic nerve
  • Autoimmune disorder of autonomic nervous system
  • Autonomic disorder caused by acrylamide
  • Autonomic disorder caused by heavy metal
  • Autonomic disorder caused by marine toxin
  • Autonomic disorder caused by organic solvent
  • Autonomic disorder caused by pyriminil
  • Autonomic disorder co-occurrent and due to Chagas disease
  • Autonomic disorder due to autoimmune encephalitis
  • Autonomic disorder due to botulism
  • Autonomic disorder due to encephalitis
  • Autonomic disorder due to HIV infection
  • Autonomic disorder due to leprosy
  • Autonomic disorder due to metabolic disorder
  • Autonomic disorder due to multiple sclerosis
  • Autonomic disorder due to Parkinson disease
  • Autonomic disorder due to prion disease
  • Autonomic disorder due to stimulant intoxication
  • Autonomic disorder due to substance withdrawal
  • Autonomic disorder due to tetanus
  • Autonomic nervous system disorder co-occurrent and due to neurodegenerative disorder
  • Autonomic neuropathy
  • Chagas' disease with nervous system involvement
  • Disorder of autonomic nerve due to Guillain-Barre Syndrome
  • Disorder of autonomic nerve due to impaired glucose tolerance
  • Disorder of autonomic nervous system
  • Disorder of autonomic nervous system caused by drug
  • Disorder of autonomic nervous system due to infectious disease
  • Disorder of autonomic nervous system due to senile dementia of Lewy body type
  • Disorder of parasympathetic nervous system
  • Disorder of peripheral autonomic nervous system
  • Disorder of sympathetic nervous system
  • Drug-induced autonomic dysfunction
  • Genetic syndromic childhood obesity
  • Hyperhidrosis due to autonomic dysregulation
  • Hypohidrosis
  • Hypohidrosis co-occurrent and due to disorder of sympathetic nervous system
  • Hypohidrosis due to neurological disorder
  • Inherited autonomic nervous system disorder
  • Paraneoplastic autonomic dysfunction
  • Paraneoplastic neuropathy
  • Primary autonomic disorder with acquired anhidrosis
  • Rapid-onset childhood obesity, hypothalamic dysfunction, hypoventilation, autonomic dysregulation syndrome

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Degeneration, degenerative
      • nervous system
        • autonomic
    • Disease, diseased
      • nervous system
        • autonomic
    • Disease, diseased
      • nervous system
        • parasympathetic
    • Disease, diseased
      • nervous system
        • sympathetic
    • Disease, diseased
      • nervous system
        • vegetative
    • Disease, diseased
      • peripheral
        • autonomic nervous system
    • Disease, diseased
      • sympathetic nervous system
    • Disorder(of)
      • autonomic nervous system
    • Disorder(of)
      • nerve
        • sympathetic
    • Disorder(of)
      • nervous system
        • autonomic (peripheral)
    • Disorder(of)
      • nervous system
        • parasympathetic
    • Disorder(of)
      • nervous system
        • sympathetic
    • Disorder(of)
      • nervous system
        • vegetative
    • Disturbance(s)
      • sympathetic (nerve)
    • Neuropathy, neuropathic
      • peripheral (nerve)
        • autonomic

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR NVS020
Other nervous system disorders (neither hereditary nor degenerative)
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Hypohidrosis

    abnormally diminished or absent perspiration. both generalized and segmented (reduced or absent sweating in circumscribed locations) forms of the disease are usually associated with other underlying conditions.

  • Autonomic Neuropathy, CTCAE

    a disorder characterized by damage to nerves that control your internal organs.

  • Grade 1 Autonomic Neuropathy, CTCAE

    mild symptoms

  • Grade 2 Autonomic Neuropathy, CTCAE

    moderate symptoms; limiting instrumental adl or mild/moderate impact on age-appropriate normal daily activity (pediatric)

  • Grade 3 Autonomic Neuropathy, CTCAE

    severe symptoms; limiting self-care adl or severe impact on age-appropriate normal daily activity (pediatric)

  • Grade 4 Autonomic Neuropathy, CTCAE

    life-threatening consequences; urgent intervention indicated

  • Grade 5 Autonomic Neuropathy, CTCAE

    death

  • Grade 2 Hypohidrosis, CTCAE|Grade 2 Hypohidrosis

    symptomatic; limiting instrumental adl or mild/moderate impact on age-appropriate normal daily activity (pediatric)

  • Grade 3 Hypohidrosis, CTCAE|Grade 3 Hypohidrosis

    increase in body temperature; limiting self-care adl or severe impact on age-appropriate normal daily activity (pediatric)

  • Grade 4 Hypohidrosis, CTCAE|Grade 4 Hypohidrosis

    life-threatening consequences; urgent intervention indicated

  • Autonomic Neuropathy

    an inherited or acquired peripheral neuropathy affecting the autonomic nervous system. it results in disruption of the involuntary body functions. inherited causes include fabry disease and porphyrias. acquired causes include diabetes, uremia, hepatic disorders, vitamin deficiencies, toxins, and drug toxicities.

  • Diabetic Autonomic Neuropathy

    autonomic neuropathy that is caused by diabetes mellitus.

  • ELP1 wt Allele|DYS|Dysautonomia (Riley-Day Syndrome, Hereditary Sensory Autonomic Neuropathy Type III) Gene|ELP1, Yeast, Homolog of Gene|Elongator Acetyltransferase Complex Subunit 1 wt Allele|Elongator Acetyltransferase Complex, Subunit 1 Gene|FD|IKAP|IKBKAP|IKI3|Inhibitor of Kappa Light Polypeptide Gene Enhancer In B-Cells, Kinase Complex-Associated Protein Gene|TOT1

    human elp1 wild-type allele is located in the vicinity of 9q31.3 and is approximately 67 kb in length. this allele, which encodes elongator complex protein 1, plays a role in the modification of trna. mutation of the gene is associated with familial dysautonomia and predisposition for medulloblastoma.

  • Familial Dysautonomia|Familial dysautonomia|HSAN 3|HSAN III|Hereditary Sensory and Autonomic Neuropathy Type III|Neuropathy, Hereditary Sensory and Autonomic, Type III|Riley- Day|Riley-Day Syndrome|hereditary sensory and autonomic neuropathy type III

    a congenital disorder caused by mutations in the ikbkap gene. it is characterized by damage of the sympathetic and parasympathetic and sensory nervous system.

  • Neuropathy, Hereditary Sensory and Autonomic, Type I|HSAN1|Hereditary Sensory and Autonomic Neuropathy Type 1

    an autosomal dominant condition caused by mutation(s) in the sptlc1 gene, encoding serine palmitoyltransferase long chain base subunit 1. it is characterized by distal sensory impairment with variable autonomic and motor involvement.

  • Neuropathy, Hereditary Sensory and Autonomic, Type IV|CIPA|Congenital Insensitivity to Pain with Anhidrosis|HSAN4|Hereditary Sensory and Autonomic Neuropathy Type IV

    a rare, autosomal recessive inherited disorder caused by mutations in the ntrk1 gene. it is characterized by inability to feel pain and temperature that leads to repeated unintentional self-injuries, and decreased or absent sweating that leads to hyperpyrexia and febrile seizures.

  • Neuropathy, Hereditary Sensory and Autonomic, Type V|HSAN5|Hereditary Sensory and Autonomic Neuropathy Type V

    an autosomal recessive condition caused by mutation(s) in the ngf gene, encoding beta-nerve growth factor. it is characterized by loss of pain sensation, particularly in the extremities.

  • Neuropathy, Hereditary Sensory and Autonomic, Type VII|HSAN7|Hereditary Sensory and Autonomic Neuropathy Type VII

    a very rare disorder caused by mutation in the scn11a gene. affected individuals are unable to experience pain since birth resulting in self-inflicted injuries.

  • Grade 2 Hypohidrosis, CTCAE|Grade 2 Hypohidrosis

    symptomatic; limiting instrumental adl

  • Grade 3 Hypohidrosis, CTCAE|Grade 3 Hypohidrosis

    increase in body temperature; limiting self care adl

  • Grade 4 Hypohidrosis, CTCAE|Grade 4 Hypohidrosis

    heat stroke

  • Grade 5 Hypohidrosis, CTCAE|Grade 5 Hypohidrosis

    death

  • Hypohidrosis

    reduced sweating. causes include burns, dehydration, radiation, and leprosy.

  • Hypohidrosis, CTCAE|Hypohidrosis|Hypohidrosis

    a disorder characterized by reduced sweating.

Patient EducationClinical

Autonomic Nervous System Disorders

Your autonomic nervous system is the part of your nervous system that controls involuntary actions, such as the beating of your heart and the widening or narrowing of your blood vessels. When something goes wrong in this system, it can cause serious problems, including:

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert G90.9 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
337.9 Autonomic nerve dis NEC
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About G90.9Overview

Is G90.9 (Disorders of autonomic nervous system) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report disorder of the autonomic nervous system, unspecified on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What is the ICD-9 equivalent of G90.9?

Under the General Equivalence Mappings, disorder of the autonomic nervous system, unspecified converts to ICD-9-CM 337.9 (autonomic nerve dis NEC). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.