G81.00

Flaccid hemiplegia affecting unspecified side

FY2027Chapter 6: Diseases of the nervous system/G80–G83 Cerebral palsy and other paralytic syndromes

BillableComplete code, valid to report

G81.00 (also written G8100) is a billable ICD-10-CM diagnosis code for flaccid hemiplegia affecting unspecified side. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 15 codes in category G81 (Hemiplegia and hemiparesis). Its coding notes include 2 Excludes1 entries and 8 Excludes2 entries.

Guidelines tip

From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.

These codes identify whether the dominant or nondominant side is affected. The Guidelines give defaults when the side is documented but dominance is not.

Guidelines I.C.9.d.1; I.C.6.aHemiplegia and monoplegia: dominant and nondominant sideRead the official text

Excludes1

Not coded here. The listed conditions generally should not be reported together.

Inherited from G81 Hemiplegia and hemiparesis

Excludes2

Not included here. Both codes may be reported if the patient has both conditions.

Also from chapter/block level (8 notes)
Inherited from Chapter 6 Diseases of the nervous system
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

Care settings

How CMS programs treat this code. These are CMS claim edits and list entries, not coverage or eligibility rules.

Hospital CC

Counts as a complication or comorbidity (CC) when reported as a secondary diagnosis on an inpatient claim. It does not count when the principal diagnosis is one of the 138 codes in its exclusion list. Some MS-DRGs also ignore a CC or MCC that defines the DRG.

Source: CMS MS-DRG Definitions Manual v44, effective October 1, 2026, Appendix C

IPF Primary

IPF MS-DRG adjustment. A principal diagnosis of this code groups to one of these MS-DRGs. Which one depends on other facts of the stay, so the factor is a range:

MS-DRGDescriptionFactor
056Degenerative nervous system disorders w MCC1.12
057Degenerative nervous system disorders w/o MCC1.11
A principal diagnosis that groups to none of the 19 designated MS-DRGs gets no MS-DRG adjustment. Otherwise the claim still receives the federal per diem base rate and the other adjustments.

Source: CMS IPF PPS FY 2027 final rule (CMS-1847-F), Addendum A; code lists from the CMS MS-DRG Definitions Manual v44; effective for discharges on or after October 1, 2026

Notes

Inherited from G81 Hemiplegia and hemiparesis
  • This category is to be used only when hemiplegia (complete)(incomplete) is reported without further specification, or is stated to be old or longstanding but of unspecified cause. The category is also for use in multiple coding to identify these types of hemiplegia resulting from any cause.