2027 ICD-10-CM Diagnosis Code R29.90Unspecified symptoms and signs involving the nervous system
ICD-10-CM Codes›R00–R99›R25-R29›R29
- Billable — Valid for Submission
- Not Chronic
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 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 91 through 93. As a symptom code, it should not be used as a principal diagnosis once a related definitive diagnosis has been established. Coders also document this condition as central nervous system deficit. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Nervous system signs and symptoms.
Code Identity
Code Classification
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 symptom
- Transient neurological symptoms
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to R29.90: its own notes plus those printed at Chapter 18. A note printed at a category, block or chapter applies to every code under it.
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
Notes
General instructions on how these codes are used.
- This chapter includes symptoms, signs, abnormal results of clinical or other investigative procedures, and ill-defined conditions regarding which no diagnosis classifiable elsewhere is recorded.
- Signs and symptoms that point rather definitely to a given diagnosis have been assigned to a category in other chapters of the classification. In general, categories in this chapter include the less well-defined conditions and symptoms that, without the necessary study of the case to establish a final diagnosis, point perhaps equally to two or more diseases or to two or more systems of the body. Practically all categories in the chapter could be designated 'not otherwise specified', 'unknown etiology' or 'transient'. The Alphabetical Index should be consulted to determine which symptoms and signs are to be allocated here and which to other chapters. The residual subcategories, numbered .8, are generally provided for other relevant symptoms that cannot be allocated elsewhere in the classification.
- The conditions and signs or symptoms included in categories R00-R94 consist of:
- (a) cases for which no more specific diagnosis can be made even after all the facts bearing on the case have been investigated;
- (b) signs or symptoms existing at the time of initial encounter that proved to be transient and whose causes could not be determined;
- (c) provisional diagnosis in a patient who failed to return for further investigation or care;
- (d) cases referred elsewhere for investigation or treatment before the diagnosis was made;
- (e) cases in which a more precise diagnosis was not available for any other reason;
- (f) certain symptoms, for which supplementary information is provided, that represent important problems in medical care in their own right.
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
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.
Code HistoryHistory
Questions About R29.90Overview
What is the ICD-10 code for unspecified symptoms and signs involving the nervous system?
The ICD-10-CM code for unspecified symptoms and signs involving the nervous system is R29.90 (sometimes written as R2990). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
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, 2026 through September 30, 2027.
What MS-DRG does R29.90 group to?
When unspecified symptoms and signs involving the nervous system is the principal diagnosis on an inpatient stay, it groups to MS-DRG 91, 92, 93, with relative weights from 0.7783 to 1.7050 depending on complications. Higher weights mean higher Medicare reimbursement.
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.
