ICD-10 Code K31.8 – Other specified diseases of stomach and duodenum (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code K31.8 – Other specified diseases of stomach and duodenum
What it is
K31.8 is used for stomach or duodenal disorders that are specified in the record but do not fit a more exact ICD-10-CM code. It is a catch-all code for documented, non-acute conditions of these organs.
Clinical signs
Clinical features vary; refer to documentation. Records may note upper abdominal discomfort, dyspepsia, or endoscopic findings involving the stomach or duodenum without a more specific diagnosis.
When to use this code
Use K31.8 when the provider clearly documents a specific stomach or duodenal disease, but no dedicated code is available. It also fits cases where the condition is named and supported, yet remains outside other listed categories. Check documentation if the wording is vague.
Do not use for
Do not use this code for nonspecific abdominal pain, symptoms only, or conditions that have a more precise ICD-10-CM code. Do not assign it when the record states gastritis, ulcer disease, or another defined diagnosis.
Coding tip
Match the provider’s exact diagnosis wording to the most specific code available before defaulting to K31.8.