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G99.0 ICD-10-CM Code: Autonomic neuropathy in diseases classified elsewhere

Compare with another code for G99.0Check this code on a claim

Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.

Coding at a Glance

Tabular directives
1 Excludes1 · 4 code-first instructions

Billable · FY2027A valid, specific ICD-10-CM code, reportable for dates of service in FY2027.

What you need to know

Source: CMS/NCHS Official ICD-10-CM tabular notes, quoted. From the CMS/NCHS tabular list for the release in force. A note the category or block publishes applies to this code too, and is marked with where it comes from.

Code firstSequence the underlying condition before this code
  • underlying disease, such as:
  • amyloidosis (E85.-)
  • gout (M1A.-, M10.-)
  • hyperthyroidism (E05.-)
Excludes1Not reported with this code unless documented as unrelated
  • diabetic autonomic neuropathy (E08-E13 with .43)

Where it sits Source: CMS/NCHS

Under:Chapter 6: Diseases of the Nervous SystemG89-G99 Other disorders of the nervous systemG99 Other disorders of nervous system in diseases classified elsewhere

Most relevant related codes MedCoder-derived

Read off the official notes above and this code’s own position in the tabular list. Which to report is a documentation question; Compare shows the two side by side.

CompareCheck ClaimView Related Codes

Inpatient Payment Groups (MS-DRG)

Potential MS-DRG participation — not a DRG assignment.

MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v44, Appendix B.

  • MS-DRG 073 — CRANIAL AND PERIPHERAL NERVE DISORDERS WITH MCC (MDC 01)
  • MS-DRG 074 — CRANIAL AND PERIPHERAL NERVE DISORDERS WITHOUT MCC (MDC 01)

A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for G99.0 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2027Effective: October 1, 2026

Trace:FY2027 changesChange historyRelease, file and checksum

Excludes1 — Not Coded Here

Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).

Code First

Underlying conditions that must be sequenced before this code.

  • underlying disease, such as:
  • amyloidosis (E85.-)
  • gout (M1A.-, M10.-)
  • hyperthyroidism (E05.-)

Coder workflow for G99.0

MedCoder structured workflow — derived from this code’s own official record

Before you code G99.0

  1. G99.0 is a manifestation code (“in diseases classified elsewhere”). Confirm the underlying condition is documented and sequence it first; a manifestation code is not reported as the first-listed or principal diagnosis. The etiology/manifestation convention (Guidelines I.A.13).

    See the official tabular notes · Guide: Manifestation codes and Code First sequencing →

  2. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with G99.0. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).

    See the official tabular notes

Choose the right path

  1. Does the documentation support a condition named in G99.0’s Excludes1 note?
    Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
    No → Continue.
  2. Is the underlying (etiologic) condition the Code First note names documented?
    Yes → Sequence the underlying condition first, then G99.0.
    No → A manifestation code needs its underlying condition — query before reporting it.

    ReviewE85, M1A, M10, E05

Consider G99.0. Then confirm the code is valid for the date of service in the Verify section.

Documentation check

The provider’s diagnostic statement
Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).
The underlying (etiologic) condition
Named in the Code First note; sequenced before this code when documented (Guidelines I.A.13).

Official instructions as workflow

  • Excludes1 — check before selecting G99.0(1 note)

    Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with G99.0: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

    See the official tabular notes · Guidelines I.A.12.a

  • Code First — sequencing check(4 notes)

    Coding workflow: Check whether the underlying or etiologic condition the note names is documented. When it is, sequence it before G99.0. Do not add an underlying condition the record does not document.

    ReviewE85, M1A, M10, E05

    See the official tabular notes · Guidelines I.A.13

Coding decision scenarios

Pattern scenarios for this code’s structure — decision rules, not clinical cases

Documentation: Both the condition G99.0 describes and a condition named in its Excludes1 note are documented for the same encounter.

Coding question: Can both codes be reported?

Path: Review the Excludes1 note and the excluded code, and look for a provider statement on whether the two conditions are related.

Reason: Excludes1 means the two are not coded together; the exception is when the record shows the conditions are unrelated to each other (Guidelines I.A.12.a).

Documentation: The underlying condition the Code First note names is documented alongside this condition.

Coding question: How are the two sequenced?

Path: Review the Code First note.

Reason: The underlying condition is sequenced first and the manifestation follows (Guidelines I.A.13).

ReviewE85, M1A, M10, E05

Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.

Don’t confuse G99.0 with…

MedCoder analysis — pairs from this code’s official notes, distinctions written by MedCoder

The codes most likely to be picked instead of G99.0 — named in its own official notes, or sharing its laterality or encounter family — with what separates them and which documentation moves the case. Each links to the full comparison.

  • E08— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of diabetic autonomic neuropathy moves the case to E08; the two are not reported together unless documented as unrelated.

    Full comparison: G99.0 vs E08 →

  • E13— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of diabetic autonomic neuropathy moves the case to E13; the two are not reported together unless documented as unrelated.

    Full comparison: G99.0 vs E13 →

Relationships are read from this code's own official notes, its laterality siblings and its encounter family; the wording of each distinction is MedCoder editorial, and the documentation named in each “what moves you there” line is the official note phrase or sibling title itself. Source: CMS ICD-10-CM tabular instructional notes; ICD-10-CM Official Guidelines, Section I.A.12.a.

Coding context

Guidelines, coding notes, decision aids, relationships (with MS-DRG and CCSR classification), hierarchy, HCC, coverage and the context map: what a coder reaches for after the core. Each section names whether it is official source data, a MedCoder-derived relationship or MedCoder editorial.

Code Overview

Autonomic neuropathy in diseases classified elsewhere is a billable ICD-10-CM diagnosis code (G99.0).

MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.

Verify Before Coding

  • Principal-diagnosis restriction. This is a manifestation code: the Medicare Code Editor requires the underlying condition (etiology) to be sequenced first, with this code reported after it.
  • CC as a secondary diagnosis (FY2027). Can raise the stay's MS-DRG severity tier.

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.

Relationships & Classification

MedCoder-derived relationships — computed from published CMS and AHRQ datasets

Other codes that name G99.0 or its code family, from the CMS ICD-10-CM tabular instructional notes and the CMS ICD-10-CM Index to Diseases and Injuries. Tabular-note edges are stored at the code family level that carries each note.

Referenced by 2 Use Additional Code instructions: M10 — Gout, M1A — Chronic gout.

These codes instruct coders to additionally report this code when it applies.

Referenced by 2 Index etiology/manifestation pairs: E34.9 — Endocrine disorder, unspecified, E88.9 — Metabolic disorder, unspecified.

The ICD-10-CM Index lists these etiology codes with this code in brackets — the manifestation, reported second.

MS-DRG Grouper Relationships (FY2027)

Potential MS-DRG participation — not a DRG assignment.

FY2027 MS-DRG: CC — Complication or Comorbidity. Reported as a secondary diagnosis, this code raises the stay's MS-DRG severity tier — except when the principal diagnosis is one of 25 clinically related codes on its CMS exclusion list.

Named in the grouper logic of 2 MS-DRGs: DRG 073 (MDC 01), DRG 074 (MDC 01).

From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.

Clinical classification (AHRQ CCSR):NVS006 — Other nervous system disorders (often hereditary or degenerative).

Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.

Related Codes

Same clinical process (MS-DRG)

Acts as CC — raises the severity of other admissions. CMS groups these diagnoses into one MS-DRG principal-diagnosis exclusion process — a CC/MCC on this list never raises severity when the principal diagnosis is also on it.

G90.512 — Complex regional pain syndrome I of left upper limb, G90.513 — Complex regional pain syndrome I of upper limb, bilateral, G90.519 — Complex regional pain syndrome I of unspecified upper limb, G90.521 — Complex regional pain syndrome I of right lower limb, G90.522 — Complex regional pain syndrome I of left lower limb, G90.523 — Complex regional pain syndrome I of lower limb, bilateral, G90.529 — Complex regional pain syndrome I of unspecified lower limb, G90.59 — Complex regional pain syndrome I of other specified site, G90.81 — Serotonin syndrome, G90.89 — Other disorders of autonomic nervous system, G90.9 — Disorder of the autonomic nervous system, unspecified, G90.B — LMNB1-related autosomal dominant leukodystrophy, G93.40 — Encephalopathy, unspecified, G93.41 — Metabolic encephalopathy, G93.42 — Megalencephalic leukoencephalopathy with subcortical cysts, G93.43 — Leukoencephalopathy with calcifications and cysts, G93.44 — Adult-onset leukodystrophy with axonal spheroids, G93.45 — Developmental and epileptic encephalopathy, G93.49 — Other encephalopathy, I67.83 — Posterior reversible encephalopathy syndrome, +5 more

Principal diagnosis restriction (Medicare Code Editor)

Manifestation code — the underlying condition is sequenced first.

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Other nervous system disorders (often hereditary or degenerative)).

G31.84 — Mild cognitive impairment of uncertain or unknown etiology, G31.85 — Corticobasal degeneration, G31.86 — Alexander disease, G31.87 — Primary progressive apraxia of speech, G31.89 — Other specified degenerative diseases of nervous system, G31.9 — Degenerative disease of nervous system, unspecified, G32.0 — Subacute combined degeneration of spinal cord in diseases classified elsewhere, G32.81 — Cerebellar ataxia in diseases classified elsewhere, G32.89 — Other specified degenerative disorders of nervous system in diseases classified elsewhere, G90.01 — Carotid sinus syncope, G90.09 — Other idiopathic peripheral autonomic neuropathy, G90.1 — Familial dysautonomia [Riley-Day], G90.3 — Multi-system degeneration of the autonomic nervous system, G90.4 — Autonomic dysreflexia, G90.B — LMNB1-related autosomal dominant leukodystrophy, G93.42 — Megalencephalic leukoencephalopathy with subcortical cysts, G93.43 — Leukoencephalopathy with calcifications and cysts, G93.44 — Adult-onset leukodystrophy with axonal spheroids, G93.45 — Developmental and epileptic encephalopathy, G99.2 — Myelopathy in diseases classified elsewhere, +83 more

Contextual Map

Every relationship of G99.0 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Run G99.0 with these 9 related codes in Claim Check

Hierarchy

Excludes1

Code First

  • E05 — Thyrotoxicosis [hyperthyroidism][Code First]: “hyperthyroidism (E05.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2027
  • E85 — Amyloidosis[Code First]: “amyloidosis (E85.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2027
  • M10 — Gout[Code First]: “gout (M1A.-, M10.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2027
  • M1A — Chronic gout[Code First]: “gout (M1A.-, M10.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2027

Referenced by Use Additional Code instructions

  • M10 — Gout[Use Additional Code]: “Autonomic neuropathy in diseases classified elsewhere (G99.0)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2027
  • M1A — Chronic gout[Use Additional Code]: “Autonomic neuropathy in diseases classified elsewhere (G99.0)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2027

Referenced by Index etiology/manifestation pairs

  • E34.9 — Endocrine disorder, unspecified[Index manifestation]: “Neuropathy, neuropathic, peripheral, autonomic, in, endocrine disease NEC”— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027
  • E88.9 — Metabolic disorder, unspecified[Index manifestation]: “Neuropathy, neuropathic, peripheral, autonomic, in, metabolic disease NEC”— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027

Clinical classification (CCSR)

MS-DRG Grouper

MDC crossing

  • MDC 01 — Diseases and Disorders of the Nervous System[MDC crossing]: “Diseases and Disorders of the Nervous System — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs. 8,919 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2027

Nearest codes

Change history

  • FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016

Reference

Index terms and tables, published questions and FAQ, every source behind this page with its release and checksum, the date-of-service check and the complete change history.

Sources for this page

Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.

Code, title, tabular notes and index terms Official source data
CMS/CDC ICD-10-CM FY2027 tabular list, index and tables, effective October 1, 2026 Release, file and checksum · Publisher’s page
Claim edits Official source data
CMS Definitions of Medicare Code Edits — v44.0 (October 2026) Release, file and checksum · Publisher’s page
Inpatient payment groups Official source data
CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v44 Release, file and checksum · Publisher’s page
Change history and date-of-service validity Official source data
CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
Comparisons, relationships and the contextual map MedCoder-derived relationship
Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
Summary and FAQ answers MedCoder editorial explanation
Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.

Current data releases:ICD-10-CM FY2027 · ICD-10-PCS FY2027 · HCPCS October 2026 · MS-DRG v44 · Medicare Code Editor v44.0 · NCCI PTP Q4 2026 · MUE Q4 2026 · NCD code lists 2026-01 · LCD export September 28, 2026 · All releases and sources

Labels on this page: Official source data · MedCoder-derived relationship · MedCoder editorial explanation. How to read the labels · All data sources and release dates · CMS coding rules

Cite this page

Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.

MedCoder.ai. "G99.0 — Autonomic neuropathy in diseases classified elsewhere." ICD-10-CM FY2027. https://medcoder.ai/icd10/code/g99.0-autonomic-neuropathy-in-diseases-classified-elsewhere

Change history

  • FY2016 — October 1, 2015
    In the code set at ICD-10-CM adoption
    Autonomic neuropathy in diseases classified elsewhere

No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027, and none are recorded for this code. Note changes are tracked from FY2027 only.

Nearest Codes in This Family

Official ICD-10-CM classifications closest to G99.0 in its code family, with their registry titles.

View all codes in the G99 family