ICD-10 Code K29.0 – Acute gastritis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code K29.0 – Acute gastritis
What it is
K29.0 identifies acute gastritis, which means sudden inflammation of the stomach lining. Use it when the record documents an acute gastric inflammatory process rather than a chronic or unspecified stomach condition.
Clinical signs
Clinical features vary; refer to documentation. Commonly recorded findings may include upper abdominal pain, nausea, vomiting, or stomach tenderness, but you should code only what the provider documents.
When to use this code
Use K29.0 when the clinician clearly diagnoses acute gastritis or documents an acute inflammatory gastritis episode. It is appropriate when the note distinguishes the condition from chronic gastritis, peptic ulcer disease, or nonspecific dyspepsia. Check documentation if the cause is not stated.
Do not use for
Do not use K29.0 for chronic gastritis, unspecified gastritis, or isolated stomach pain without a confirmed diagnosis. If the record supports another gastric disorder, code that condition instead.
Coding tip
Look for the word “acute” in the assessment and verify whether the provider named a cause or a different gastritis type.