2026 ICD-10-CM Diagnosis Code H00.023Hordeolum internum right eye, unspecified eyelid

ICD-10-CM Codes›H00–H59›H00-H05›H00

ICD-10-CM H00.023
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

H00.023 is a billable ICD-10-CM diagnosis code for hordeolum internum right eye, unspecified eyelid. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 124 through 125. Coders also document this condition as acute blepharitis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Cornea and external disease.

Code Identity

ICD-10-CM Code
H00.023
Billable Status
Yes — Valid for Submission
Code Describes
Hordeolum internum right eye, unspecified eyelid
Short Description
Hordeolum internum right eye, unspecified eyelid
Same as the full description in the CMS dataset.
Parent Code
H00.02
Hordeolum internum

Code Classification

ChapterH00–H59Diseases of the eye and adnexa
SectionH00-H05Disorders of eyelid, lacrimal system and orbit
CategoryH00Hordeolum and chalazion
This CodeH00.023Hordeolum internum right eye, unspecified eyelid

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute blepharitis
  • Hordeolum internum of right eye
  • Internal hordeolum
  • Meibomianitis of right eyelid

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.

    • Hordeolum(eyelid) (externum) (recurrent)
      • internum
        • right

Clinical ClassificationClinical

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

CCSR EYE001
Cornea and external disease
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Eyelid Disorders

Your eyelids help protect your eyes. When you blink, your eyelids spread moisture over your eyes. Blinking also helps move dirt or other particles off the surface of the eye. You close your eyelids when you see something coming toward your eyes. This can help protect against injuries.

Read the full article at MedlinePlus

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

Convert H00.023 to ICD-9-CMHistory

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

ICD-9-CM
373.12 Hordeolum internum
Approximate The match is approximate rather than exact.

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 H00.023Overview

Is H00.023 (Hordeolum internum) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report hordeolum internum right eye, unspecified eyelid on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does H00.023 group to?

When hordeolum internum right eye, unspecified eyelid is the principal diagnosis on an inpatient stay, it groups to MS-DRG 124, 125, with relative weights from 0.7678 to 1.3231 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of H00.023?

Under the General Equivalence Mappings, hordeolum internum right eye, unspecified eyelid converts to ICD-9-CM 373.12 (hordeolum internum). The mapping is approximate, so confirm the match fits the documentation.

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.