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ICD-10-CM 2027 diagnosis code

G90.1Familial dysautonomia [Riley-Day]

✓ Billable / specific

G90.1 is a valid, billable ICD-10-CM code for familial dysautonomia [riley-day]. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.

Looking up by condition? See ICD-10 code for Dysautonomia, ICD-10 code for Riley-Day syndrome.

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About G90.1

G90.1 is the ICD-10-CM diagnosis code for familial dysautonomia [Riley-Day]. It belongs to category G90 (disorders of autonomic nervous system), block G89-G99 (other disorders of the nervous system) and chapter 6 (diseases of the nervous system). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within G90 (disorders of autonomic nervous system), G90.1 is specifically for familial dysautonomia [Riley-Day]. Related codes cover idiopathic peripheral autonomic neuropathy (G90.0), Horner's syndrome (G90.2), Multi-system degeneration of the autonomic nervous system (G90.3), autonomic dysreflexia (G90.4), complex regional pain syndrome I (CRPS I) (G90.5), other disorders of autonomic nervous system (G90.8), disorder of the autonomic nervous system, unspecified (G90.9), postural orthostatic tachycardia syndrome [POTS] (G90.A) and 1 more.

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

In MS-DRG v44.0, it is part of the grouping logic for DRG 091 (Other Disorders of Nervous System with MCC, relative weight 1.7046), DRG 092 (Other Disorders of Nervous System with CC, relative weight 1.0239), DRG 093 (Other Disorders of Nervous System without CC/MCC, relative weight 0.7783), DRG 791 (Prematurity with Major Problems, relative weight 4.1075) and DRG 793 (Full Term Neonate with Major Problems, relative weight 4.2195), in MDC 01 (Diseases and Disorders of the Nervous System) and MDC 15 (Newborns and Other Neonates with Conditions Originating in the Perinatal Period), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 742.8 (other specified congenital anomalies of nervous system).

Notes that apply from higher levels

Instructions written at a parent level also apply to G90.1.

› From G90 Disorders of autonomic nervous system
Excludes1
  • dysfunction of the autonomic nervous system due to alcohol (G31.2)

Broader instructions also apply from Chapter 6: Diseases of the nervous system.

Alphabetic index entries

2 entries

Terms in the official ICD-10-CM index that lead to G90.1.

Codes whose notes reference G90.1

MS-DRG v44.0 grouping

All DRGs →

Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.

MDC 15 · Newborns and Other Neonates with Conditions Originating in the Perinatal Period

MDC 15 · Newborns and Other Neonates with Conditions Originating in the Perinatal Period

ICD-9-CM equivalent

Converter →
  • 742.8Other specified congenital anomalies of nervous systemapproximate

From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.

Code history

  1. 2016
  2. 2017
  3. 2018
  4. 2019
  5. 2020
  6. 2021
  7. 2022
  8. 2023
  9. 2024
  10. 2025
  11. 2026
  12. 2027
  • FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
  • No changes since FY2016.

Common questions about G90.1

Is G90.1 billable?

Yes. G90.1 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).

Can G90.1 be used as a principal diagnosis?

Yes. The Medicare Code Editor doesn't restrict G90.1 as a principal diagnosis.

Is G90.1 a CC or MCC?

No. G90.1 is neither a CC nor an MCC under MS-DRG v44.0.

What DRG does G90.1 group to?

G90.1 is used in the MS-DRG v44.0 logic for MS-DRG 091 (Other Disorders of Nervous System with MCC), MS-DRG 092 (Other Disorders of Nervous System with CC), MS-DRG 093 (Other Disorders of Nervous System without CC/MCC), MS-DRG 791 (Prematurity with Major Problems) and MS-DRG 793 (Full Term Neonate with Major Problems). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.

What is the ICD-9 code for G90.1?

The CMS General Equivalence Mappings map G90.1 to ICD-9-CM 742.8.