ICD-10-CM 2027 diagnosis code
G25.3Myoclonus
G25.3 is a valid, billable ICD-10-CM code for myoclonus. 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 Jerks, ICD-10 code for Myoclonus, ICD-10 code for Paramyoclonus multiplex.
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 G25.3
G25.3 is the ICD-10-CM diagnosis code for myoclonus. It belongs to category G25 (other extrapyramidal and movement disorders), block G20-G26 (extrapyramidal and movement disorders) 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 G25 (other extrapyramidal and movement disorders), G25.3 is specifically for myoclonus. Related codes cover essential tremor (G25.0), drug-induced tremor (G25.1), other specified forms of tremor (G25.2), drug-induced chorea (G25.4), other chorea (G25.5), drug induced tics and other tics of organic origin (G25.6), other and unspecified drug induced movement disorders (G25.7), other specified extrapyramidal and movement disorders (G25.8) and 1 more.
Don't report G25.3 together with the conditions in its Excludes1 note: facial myokymia (G51.4) and myoclonic epilepsy (G40.-).
Use an additional code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5).
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) and DRG 093 (Other Disorders of Nervous System without CC/MCC, relative weight 0.7783), in MDC 01 (Diseases and Disorders of the Nervous System), 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 333.2 (myoclonus).
Coding notes
- Drug-induced myoclonus
- Palatal myoclonus
Notes that apply from higher levels
Instructions written at a parent level also apply to G25.3.
› From G25 Other extrapyramidal and movement disorders
- sleep related movement disorders (G47.6-)
Broader instructions also apply from Chapter 6: Diseases of the nervous system.
Alphabetic index entries
12 entriesTerms in the official ICD-10-CM index that lead to G25.3.
- Convulsions (idiopathic) › myoclonic
- Disease, diseased › Friedreich's › myoclonia
- Jerks, myoclonic
- Myoclonus, myoclonic, myoclonia (familial) (essential) (multifocal) (simplex)
- Myoclonus, myoclonic, myoclonia (familial) (essential) (multifocal) (simplex) › drug-induced
- Myoclonus, myoclonic, myoclonia (familial) (essential) (multifocal) (simplex) › familial progressive
- Myoclonus, myoclonic, myoclonia (familial) (essential) (multifocal) (simplex) › Friedreich's
- Myoclonus, myoclonic, myoclonia (familial) (essential) (multifocal) (simplex) › jerks
- Myoclonus, myoclonic, myoclonia (familial) (essential) (multifocal) (simplex) › massive
- Myoclonus, myoclonic, myoclonia (familial) (essential) (multifocal) (simplex) › palatal
- Myoclonus, myoclonic, myoclonia (familial) (essential) (multifocal) (simplex) › pharyngeal
- Paramyoclonus multiplex
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 01 · Diseases and Disorders of the Nervous System
ICD-9-CM equivalent
Converter →- 333.2Myoclonusexact
From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about G25.3
Is G25.3 billable?
- Yes. G25.3 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can G25.3 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict G25.3 as a principal diagnosis.
Is G25.3 a CC or MCC?
- No. G25.3 is neither a CC nor an MCC under MS-DRG v44.0.
What DRG does G25.3 group to?
- G25.3 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) and MS-DRG 093 (Other Disorders of Nervous System without CC/MCC). 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 G25.3?
- The CMS General Equivalence Mappings map G25.3 to ICD-9-CM 333.2.