2026 ICD-10-CM Diagnosis Code J45.40Moderate persistent asthma, uncomplicated

ICD-10-CM Codes›J00–J99›J40-J4A›J45

ICD-10-CM J45.40
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

J45.40 is a billable ICD-10-CM diagnosis code for moderate persistent 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. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Asthma.

J45.40 does not risk-adjust for Medicare Advantage under the CMS-HCC V28 model. It still risk-adjusts in the RxHCC Part D (V08) category 229 for payment year 2026.

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

Code Identity

ICD-10-CM Code
J45.40
Billable Status
Yes — Valid for Submission
Code Describes
Moderate persistent asthma, uncomplicated
Short Description
Moderate persistent asthma, uncomplicated
Same as the full description in the CMS dataset.
Parent Code
J45.4
Moderate persistent asthma

Code Classification

ChapterJ00–J99Diseases of the respiratory system
SectionJ40-J4AChronic lower respiratory diseases
CategoryJ45Asthma
This CodeJ45.40Moderate persistent asthma, uncomplicated

Medicare Risk Adjustment (HCC)Billing

J45.40 does not risk-adjust for Medicare Advantage under the CMS-HCC V28 model, but it maps to payment categories in the other CMS models shown below.

CMS-HCC V28 (Medicare Advantage Payment Model)
Not mapped
no payment category in the model that pays 100% of MA risk scores
Prior Model (CMS-HCC V24)
Not mapped under V24
this diagnosis newly risk-adjusts under the V28 model
Part D (RxHCC)
RxHCC 229 — Chronic Obstructive Pulmonary Disease, Bronchiectasis, and Other Asthma
also risk-adjusts in the Part D prescription drug model (V08)

Source: CMS Payment Year 2026 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Moderate asthma
  • Moderate persistent allergic asthma
  • Moderate persistent allergic asthma controlled
  • Moderate persistent allergic asthma uncontrolled
  • Moderate persistent asthma
  • Moderate persistent asthma controlled
  • Moderate persistent asthma co-occurrent with allergic rhinitis
  • Moderate persistent asthma uncontrolled
  • Moderate persistent asthma uncontrolled co-occurrent with allergic rhinitis
  • Moderate persistent controlled asthma co-occurrent with allergic rhinitis
  • Uncomplicated asthma
  • Uncomplicated moderate persistent asthma
  • Uncontrolled asthma

Tabular List NotesGuidance

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

Inclusion Terms

  • Moderate persistent asthma NOS

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

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 J45.40 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 J45.40Overview

What is the ICD-10 code for moderate persistent asthma, uncomplicated?

The ICD-10-CM code for moderate persistent asthma, uncomplicated is J45.40 (sometimes written as J4540). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Is J45.40 (Moderate persistent asthma) a billable code?

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

What MS-DRG does J45.40 group to?

When moderate persistent 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 J45.40?

Under the General Equivalence Mappings, moderate persistent 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.

Does J45.40 risk-adjust for Medicare Advantage payment?

Not for Medicare Advantage: J45.40 maps to no category in the CMS-HCC V28 model. It still risk-adjusts in the RxHCC Part D (V08) category 229 (Chronic Obstructive Pulmonary Disease, Bronchiectasis, and Other Asthma).