2026 ICD-10-CM Diagnosis Code K29.00Acute gastritis without bleeding

ICD-10-CM Codes›K00–K95›K20-K31›K29

ICD-10-CM K29.00
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

K29.00 is a billable ICD-10-CM diagnosis code for acute gastritis without bleeding. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 391 through 392. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Gastritis and duodenitis.

Code Identity

ICD-10-CM Code
K29.00
Billable Status
Yes — Valid for Submission
Code Describes
Acute gastritis without bleeding
Short Description
Acute gastritis without bleeding
Same as the full description in the CMS dataset.
Parent Code
K29.0
Acute gastritis

Code Classification

ChapterK00–K95Diseases of the digestive system
SectionK20-K31Diseases of esophagus, stomach and duodenum
CategoryK29Gastritis and duodenitis
This CodeK29.00Acute gastritis without bleeding

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute and chronic gastritis
  • Acute erosive gastritis
  • Acute gastritis
  • Acute neutrophilic gastritis
  • Acute superficial gastritis
  • Caustic injury gastritis
  • Corrosive gastritis
  • Erosive gastritis
  • Gastrointestinal sequelae of disorders
  • Superficial gastritis
  • Toxic gastritis

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.

    • Gastritis(simple)
      • acute (erosive)

Clinical ClassificationClinical

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

CCSR DIG007
Gastritis and duodenitis
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Erosive Gastritis

    gastritis that is characterized by erosion of the mucosal surface.

  • Acute Gastritis

    acute inflammation of the stomach.

Patient EducationClinical

Stomach Disorders

Your stomach is an organ between your esophagus and small intestine. It is where digestion of protein begins. The stomach has three tasks. It stores swallowed food. It mixes the food with stomach acids. Then it sends the mixture on to the small intestine.

Read the full article at MedlinePlus

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

Convert K29.00 to ICD-9-CMHistory

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

ICD-9-CM
535.00 Acute gastrtis w/o hmrhg
Exact Match The mapping is direct, with no qualifiers.

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 K29.00Overview

Is K29.00 (Acute gastritis) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report acute gastritis without bleeding on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does K29.00 group to?

When acute gastritis without bleeding is the principal diagnosis on an inpatient stay, it groups to MS-DRG 391, 392, with relative weights from 0.7796 to 1.2683 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of K29.00?

Under the General Equivalence Mappings, acute gastritis without bleeding converts to ICD-9-CM 535.00 (acute gastrtis w/o hmrhg). 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.