2026 ICD-10-CM Diagnosis Code R29.90Unspecified symptoms and signs involving the nervous system

ICD-10-CM Codes›R00–R99›R25-R29›R29

ICD-10-CM R29.90
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

R29.90 is a billable ICD-10-CM diagnosis code for unspecified symptoms and signs involving the nervous system. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). As a symptom code, it should not be used as a principal diagnosis once a related definitive diagnosis has been established. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Nervous system signs and symptoms.

Code Identity

ICD-10-CM Code
R29.90
Billable Status
Yes — Valid for Submission
Code Describes
Unspecified symptoms and signs involving the nervous system
Short Description
Unspecified symptoms and signs involving the nervous system
Same as the full description in the CMS dataset.
Parent Code
R29.9
Unspecified symptoms and signs involving the nervous and musculoskeletal systems

Code Classification

ChapterR00–R99Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified
SectionR25-R29Symptoms and signs involving the nervous and musculoskeletal systems
CategoryR29Other symptoms and signs involving the nervous and musculoskeletal systems
This CodeR29.90Unspecified symptoms and signs involving the nervous system

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Central nervous system deficit
  • Generalized hyperhidrosis
  • Generalized hyperhidrosis due to neurological disorder
  • Hypernasality syndrome
  • Hypernasality syndrome due to neurologic disease
  • Nasal resonatory disorder
  • Neurological deficit
  • Neurological disorder monitoring status
  • Neurological symptom
  • Neurological symptom changes
  • Transient neurological symptoms

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.

    • Symptoms NEC
      • involving
        • nervous system

Clinical ClassificationClinical

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

CCSR SYM010
Nervous system signs and symptoms
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Neurologic Diseases

The brain, spinal cord, and nerves make up the nervous system. Together they control all the workings of the body. When something goes wrong with a part of your nervous system, you can have trouble moving, speaking, swallowing, breathing, or learning. You can also have problems with your memory, senses, or mood.

Read the full article at MedlinePlus

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

Convert R29.90 to ICD-9-CMHistory

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

ICD-9-CM
781.99 Nerve/musculskel sym 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 R29.90Overview

Is R29.90 a billable code?

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

Can R29.90 be a principal diagnosis?

Use it with care. This is a symptom code, so once a definitive diagnosis explaining the unspecified symptoms and signs involving the nervous system is established, that condition takes the principal position instead.

What is the ICD-9 equivalent of R29.90?

Under the General Equivalence Mappings, unspecified symptoms and signs involving the nervous system converts to ICD-9-CM 781.99 (nerve/musculskel sym NEC). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.