2026 ICD-10-CM Diagnosis Code G90.3Multi-system degeneration of the autonomic nervous system

ICD-10-CM Codes›G00–G99›G89-G99›G90

ICD-10-CM G90.3
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

G90.3 is a billable ICD-10-CM diagnosis code for multi-system degeneration of the autonomic nervous system. 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 (often hereditary or degenerative).

Code Identity

ICD-10-CM Code
G90.3
Billable Status
Yes — Valid for Submission
Code Describes
Multi-system degeneration of the autonomic nervous system
Short Description
Multi-system degeneration of the autonomic nervous system
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 CodeG90.3Multi-system degeneration of the autonomic nervous system

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Amyotrophic lateral sclerosis plus syndrome
  • Amyotrophic lateral sclerosis with multiple system atrophy
  • Ataxia due to multiple system atrophy, cerebellar variant
  • Chronic hypotension
  • Chronic orthostatic hypotension
  • Dementia due to multiple system atrophy
  • Multiple system atrophy
  • Multiple system atrophy, cerebellar variant
  • Multiple system atrophy, Parkinson's variant
  • Multisystem degeneration of autonomic nervous system
  • Orthostatic hypotension
  • Orthostatic hypotension co-occurrent and due to Parkinson's disease
  • Parkinsonian syndrome with idiopathic orthostatic hypotension
  • Parkinson's disease
  • Pure autonomic failure
  • Sympathotonic orthostatic hypotension

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Neurogenic orthostatic hypotension Shy-Drager

Type 1 Excludes

  • orthostatic hypotension NOS I95.1

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
      • multi-system
    • Hypotension(arterial) (constitutional)
      • neurogenic, orthostatic
    • Hypotension(arterial) (constitutional)
      • orthostatic (chronic)
        • neurogenic
    • Parkinsonism(idiopathic) (primary)
      • with neurogenic orthostatic hypotension (symptomatic)
    • Shy-Drager syndrome

Clinical ClassificationClinical

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

CCSR NVS006
Other nervous system disorders (often hereditary or degenerative)
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Multiple System Atrophy

    a syndrome complex composed of three conditions which represent clinical variants of the same disease process: striatonigral degeneration; shy-drager syndrome; and the sporadic form of olivopontocerebellar atrophies. clinical features include autonomic, cerebellar, and basal ganglia dysfunction. pathologic examination reveals atrophy of the basal ganglia, cerebellum, pons, and medulla, with prominent loss of autonomic neurons in the brain stem and spinal cord. (from adams et al., principles of neurology, 6th ed, p1076; baillieres clin neurol 1997 apr;6(1):187-204; med clin north am 1999 mar;83(2):381-92)

  • Pure Autonomic Failure

    a degenerative disease of the autonomic nervous system that is characterized by idiopathic orthostatic hypotension and a greatly reduced level of catecholamines. no other neurological deficits are present.

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 G90.3 to ICD-9-CMHistory

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

ICD-9-CM
333.0 Degen basal ganglia 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 G90.3Overview

Is G90.3 (Disorders of autonomic nervous system) a billable code?

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

What is the ICD-9 equivalent of G90.3?

Under the General Equivalence Mappings, multi-system degeneration of the autonomic nervous system converts to ICD-9-CM 333.0 (degen basal ganglia 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.