2026 ICD-10-CM Diagnosis Code H20.00Unspecified acute and subacute iridocyclitis
ICD-10-CM Codes›H00–H59›H15-H22›H20
- Billable — Valid for Submission
- Not Chronic
H20.00 is a billable ICD-10-CM diagnosis code for unspecified acute and subacute iridocyclitis. 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. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Uveitis and ocular inflammation.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Acute anterior uveitis
- Acute anterior uveitis of bilateral eyes
- Acute anterior uveitis of left eye
- Acute anterior uveitis of right eye
- Acute cyclitis
- Acute iridocyclitis
- Acute iritis
- Acute iritis of left eye
- Acute iritis of right eye
- Anterior chamber - abnormal contents
- Bilateral acute iritis
- Bilateral subacute iridocyclitis
- Fibrin in anterior chamber
- Idiopathic acute anterior uveitis
- Idiopathic anterior uveitis
- Idiopathic subacute anterior uveitis
- Iridocyclitis of bilateral eyes
- Iritis with psoriatic arthritis
- Lepromatous anterior uveitis
- Lepromatous leprosy
- Psoriatic arthritis
- Subacute anterior uveitis
- Subacute cyclitis
- Subacute iridocyclitis
- Subacute iridocyclitis of left eye
- Subacute iridocyclitis of right eye
- Subacute iritis
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Acute Anterior Uveitis
sudden onset of anterior uveitis, usually unilateral, and associated with pain, erythema, photophobia, and blurred vision. often associated with hla-b27, with or without co-existing spondyloarthritis.
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 H20.00 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About H20.00Overview
Is H20.00 (Acute and subacute iridocyclitis) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report unspecified acute and subacute iridocyclitis on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does H20.00 group to?
When unspecified acute and subacute iridocyclitis 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 H20.00?
Under the General Equivalence Mappings, unspecified acute and subacute iridocyclitis converts to ICD-9-CM 364.00 (acute iridocyclitis NOS). 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.
