2026 ICD-10-CM Diagnosis Code J45.20Mild intermittent asthma, uncomplicated

ICD-10-CM Codes›J00–J99›J40-J4A›J45

ICD-10-CM J45.20
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

J45.20 is a billable ICD-10-CM diagnosis code for mild intermittent asthma, uncomplicated. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 202 through 203. Coders also document this condition as intermittent allergic asthma. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Asthma.

This medical diagnosis code is frequently used in Pediatrics medical specialties to designate conditions such asthma.

Code Identity

ICD-10-CM Code
J45.20
Billable Status
Yes — Valid for Submission
Code Describes
Mild intermittent asthma, uncomplicated
Short Description
Mild intermittent asthma, uncomplicated
Same as the full description in the CMS dataset.
Parent Code
J45.2
Mild intermittent asthma

Code Classification

ChapterJ00–J99Diseases of the respiratory system
SectionJ40-J4AChronic lower respiratory diseases
CategoryJ45Asthma
This CodeJ45.20Mild intermittent asthma, uncomplicated

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Intermittent allergic asthma
  • Intermittent asthma
  • Intermittent asthma co-occurrent with allergic rhinitis
  • Intermittent asthma uncontrolled
  • Intermittent asthma well controlled
  • Mild asthma
  • Mild intermittent asthma
  • Uncontrolled asthma

Tabular List NotesGuidance

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

Inclusion Terms

  • Mild intermittent asthma NOS

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.

    • Asthma, asthmatic(bronchial) (catarrh) (spasmodic)
      • intermittent (mild)
    • Asthma, asthmatic(bronchial) (catarrh) (spasmodic)
      • mild intermittent

Clinical ClassificationClinical

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

CCSR RSP009
Asthma
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Asthma

Asthma is a chronic (long-term) lung disease. It affects your airways, the tubes that carry air in and out of your lungs. When you have asthma, your airways can become inflamed and narrowed. This can cause wheezing, coughing, and tightness in your chest. When these symptoms get worse than usual, it is called an asthma attack or flare-up.

The full article covers:

  • What is asthma?
  • What causes asthma?
  • Who is at risk for asthma?
  • What are the symptoms of asthma?
  • How is asthma diagnosed?
  • What are the treatments for asthma?

Read the full article at MedlinePlus

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

Convert J45.20 to ICD-9-CMHistory

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

ICD-9-CM
493.00 Extrinsic asthma NOS
Approximate The match is approximate rather than exact.
ICD-9-CM
493.10 Intrinsic asthma NOS
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 J45.20Overview

Is J45.20 (Mild intermittent asthma) a billable code?

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

What MS-DRG does J45.20 group to?

When mild intermittent asthma, uncomplicated is the principal diagnosis on an inpatient stay, it groups to MS-DRG 202, 203, with relative weights from 0.6700 to 0.9712 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of J45.20?

Under the General Equivalence Mappings, mild intermittent asthma, uncomplicated converts to ICD-9-CM 493.00 (extrinsic asthma NOS) and 493.10 (intrinsic asthma NOS). 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.