2026 ICD-10-CM Diagnosis Code H20.019Primary iridocyclitis, unspecified eye

ICD-10-CM Codes›H00–H59›H15-H22›H20

ICD-10-CM H20.019
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

H20.019 is a billable ICD-10-CM diagnosis code for primary iridocyclitis, unspecified eye. 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. The code is flagged as an unspecified code, since codes identifying laterality exist in the same family. Coders also document this condition as primary iridocyclitis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Uveitis and ocular inflammation.

Code Identity

ICD-10-CM Code
H20.019
Billable Status
Yes — Valid for Submission
Code Describes
Primary iridocyclitis, unspecified eye
Short Description
Primary iridocyclitis, unspecified eye
Same as the full description in the CMS dataset.
Parent Code
H20.01
Primary iridocyclitis

Code Classification

ChapterH00–H59Diseases of the eye and adnexa
SectionH15-H22Disorders of sclera, cornea, iris and ciliary body
CategoryH20Iridocyclitis
This CodeH20.019Primary iridocyclitis, unspecified eye

Code EditsBilling

Medicare Code Editor checks that affect claim validity for H20.019.

Unspecified codes
Unspecified codes exist in the ICD-10-CM classification for circumstances when documentation in the medical record does not provide the level of detail needed to support reporting a more specific code. However, in the inpatient setting, there should generally be very limited and rare circumstances for which the laterality (right, left, bilateral) of a condition is unable to be documented and reported. The following pages contain the list of unspecified ICD-10-CM diagnosis codes for which there is a more specific code to identify laterality (right, left, bilateral) within that code family.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Primary iridocyclitis

Clinical ClassificationClinical

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

CCSR EYE004
Uveitis and ocular inflammation
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Eye Diseases

Even if your eyes feel healthy, you could have a problem and not know it. That's why regular eye exams are so important. Refractive errors are the most common type of vision problem that makes it hard to see clearly. But some eye conditions or diseases don't have any symptoms and can lead to a permanent loss of vision.

The full article covers:

  • What diseases can affect the eye?
  • What are the symptoms of eye diseases?
  • Who is more likely to develop eye diseases?
  • What are the treatments for eye diseases?
  • Can eye diseases be prevented?

Read the full article at MedlinePlus

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

Convert H20.019 to ICD-9-CMHistory

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

ICD-9-CM
364.01 Primary iridocyclitis
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 H20.019Overview

Is H20.019 (Primary iridocyclitis) a billable code?

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

What MS-DRG does H20.019 group to?

When primary iridocyclitis, unspecified eye 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 H20.019?

Under the General Equivalence Mappings, primary iridocyclitis, unspecified eye converts to ICD-9-CM 364.01 (primary iridocyclitis). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.