2026 ICD-10-CM Diagnosis Code R73.01Impaired fasting glucose

ICD-10-CM Codes›R00–R99›R70-R79›R73

ICD-10-CM R73.01
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

R73.01 is a billable ICD-10-CM diagnosis code for impaired fasting glucose. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 640 through 641. 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 impaired fasting glycemia. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Abnormal findings without diagnosis.

Code Identity

ICD-10-CM Code
R73.01
Billable Status
Yes — Valid for Submission
Code Describes
Impaired fasting glucose
Short Description
Impaired fasting glucose
Same as the full description in the CMS dataset.
Parent Code
R73.0
Abnormal glucose

Code Classification

ChapterR00–R99Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified
SectionR70-R79Abnormal findings on examination of blood, without diagnosis
CategoryR73Elevated blood glucose level
This CodeR73.01Impaired fasting glucose

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Impaired fasting glycemia

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Elevated fasting glucose

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.

    • Elevated, elevation
      • fasting glucose
    • Impaired, impairment(function)
      • fasting glucose

Clinical ClassificationClinical

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

CCSR SYM017
Abnormal findings without diagnosis
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Blood Glucose

Blood glucose, or blood sugar, is the main sugar found in your blood. It is your body's primary source of energy. It comes from the food you eat. Your body breaks down most of that food into glucose and releases it into your bloodstream. When your blood glucose goes up, it signals your pancreas to release insulin.

The full article covers:

  • What is blood glucose?
  • What is diabetes?
  • What are blood glucose targets?
  • When and how should I check my blood glucose?
  • What happens if my blood glucose level becomes too high?
  • What happens if my blood glucose level becomes low for me?

Read the full article at MedlinePlus

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

Convert R73.01 to ICD-9-CMHistory

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

ICD-9-CM
790.21 Impaired fasting glucose
Exact Match The mapping is direct, with no qualifiers.

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 R73.01Overview

Is R73.01 (Abnormal glucose) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report impaired fasting glucose on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does R73.01 group to?

When impaired fasting glucose is the principal diagnosis on an inpatient stay, it groups to MS-DRG 640, 641, with relative weights from 0.7782 to 1.3356 depending on complications. Higher weights mean higher Medicare reimbursement.

Can R73.01 be a principal diagnosis?

Use it with care. This is a symptom code, so once a definitive diagnosis explaining the impaired fasting glucose is established, that condition takes the principal position instead.

What is the ICD-9 equivalent of R73.01?

Under the General Equivalence Mappings, impaired fasting glucose converts to ICD-9-CM 790.21 (impaired fasting glucose). The mapping is a direct match.

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.