ICD-10 Code K26.0: Acute duodenal ulcer with hemorrhage

Key Takeaways

ICD-10 Code K26.0 describes acute duodenal ulcer with hemorrhage, a billable and specific ICD-10-CM code valid for FY2026 (effective October 1, 2025).

K26.0 falls under parent code K26 (Duodenal ulcer) in Chapter XI (K00-K95, Diseases of the digestive system); always select it over the unspecified K26.9 when hemorrhage is documented.

Code H. pylori (B96.81) and long-term NSAID use (Z79.1) as additional codes alongside K26.0 when etiology is documented in the clinical record.

Practice management software like Pabau provides structured clinical documentation tools that help gastroenterology and GI practices capture K26.0 encounter details accurately at the point of care.

ICD-10 Code K26.0 describes acute duodenal ulcer with hemorrhage – a mucosal break in the duodenum accompanied by active or recent upper gastrointestinal bleeding.

This reference covers K26.0’s billable status, its place in the K26 code hierarchy, excludes notes, additional codes for etiology, and how to distinguish it from adjacent duodenal ulcer subcodes.

ICD-10 Code K26.0: definition and billable status

ICD-10 Code K26.0 is billable and specific under the CMS ICD-10-CM classification system, meaning it can be submitted directly on a claim without further specificity. Effective October 1, 2025, the code is valid for all HIPAA-covered transactions during fiscal year 2026.

The code sits within the K26 Duodenal ulcer category, itself part of Chapter XI (K00-K95, Diseases of the digestive system). Coders working in gastroenterology, emergency medicine, or general practice should distinguish K26.0 from the broader K26.9 (duodenal ulcer unspecified) whenever hemorrhage is explicitly documented.

Pabau’s structured clinical documentation tools support accurate coding by linking clinical notes to billable diagnosis codes at the encounter level.

K26.0 code details at a glance

Use the table below for a quick reference on ICD-10 Code K26.0 before submitting a claim.

Clinical description: acute duodenal ulcer with hemorrhage

A duodenal ulcer is a mucosal erosion penetrating the wall of the duodenum, typically the first part (bulb). When classified as acute with hemorrhage, the patient’s clinical presentation includes upper GI bleeding – most commonly hematemesis, melena, or a drop in hemoglobin confirmed on endoscopy or imaging.

A CPT Code 45378 diagnostic colonoscopy is the most common way clinicians confirm the ulcer site and bleeding source.

Coders should use ICD-10 Code K26.0 only when the hemorrhage is explicitly documented by the treating clinician; inferred or suspected bleeding is not sufficient. Reliable clinical record documentation tools help capture these distinctions, so structured electronic records reduce the ambiguity that leads to claim denials.

Helicobacter pylori infection accounts for the majority of duodenal ulcers; NSAID use is the second most common cause. Both can produce acute hemorrhagic episodes. Practices offering integrative care, including those using functional medicine practice software, often investigate these root causes as part of a broader gut-health workup.

The acute qualifier in K26.0 indicates a short duration or sudden onset, distinguishing it from chronic presentations coded elsewhere in the K26 family. Clinical documentation should specify onset, duration, and endoscopic findings to support the acute designation.

Synonyms and alternate names for K26.0

ICD-10 Code K26.0 is accepted in clinical documentation under several alternate terms. All of the following map to the same billable code:

• Acute duodenal ulcer with bleeding
• Acute duodenal ulcer with haemorrhage (UK spelling variant)
• Duodenal ulcer with hemorrhage, acute
• Acute hemorrhagic duodenal ulcer
• Acute duodenal ulcer NOS with bleeding

Coders should be alert to clinical notes that use “bleeding” rather than “hemorrhage” – both terms are synonymous in the ICD-10-CM context for this code. Search the CDC/NCHS ICD-10-CM official web tool to confirm current synonym mappings if your coding software does not surface them automatically.

The same site-vs-unspecified distinction applies to ICD-10 Code K27.1, the peptic ulcer code used when the site cannot be pinned to the stomach or duodenum.

K26.0 vs other K26 subcodes: acute vs chronic duodenal ulcer coding

Selecting the right K26 subcode requires two decisions: (1) is the ulcer acute, chronic, or unspecified? and (2) does the presentation include hemorrhage, perforation, both, or neither? The full K26 family covers every combination. The table below maps all subcodes so you can confirm ICD-10 Code K26.0 is the correct selection before billing.

K26.4 is the most common subcode confusion point. When documentation is unclear on whether the ulcer is acute or long-standing but hemorrhage is present, K26.4 (chronic or unspecified with hemorrhage) is the appropriate fallback.

Reserve ICD-10 Code K26.0 for encounters where the clinical record explicitly supports the acute designation. Further guidance on distinguishing acute from chronic presentations in GI coding is available via the AAPC ICD-10-CM code lookup.

Excludes notes for ICD-10 Code K26.0

The K26 category carries an Excludes1 note that directly affects whether ICD-10 Code K26.0 is the right choice. Getting it wrong leads to claim rejections.

• Excludes1: K27.- (Peptic ulcer, site unspecified) – K27 cannot be coded at the same time as K26.0. They are mutually exclusive. If the ulcer is clearly in the duodenum, K26.0 applies; if the site is genuinely unspecified, K27.- applies instead.

Excludes1 notes signal that two codes cannot be used together because they represent the same clinical concept at different specificity levels. Always confirm the documented ulcer site before selecting between K25, K26, and K27 categories.

The HIPAA compliance requirements for electronic claim submission mean that an incorrect code submitted on a HIPAA-covered transaction can trigger an audit, not just a denial.

Coding guidelines and documentation requirements for K26.0

The ICD-10-CM Official Guidelines for Coding and Reporting, co-maintained by CMS and NCHS, govern sequencing and additional code requirements for ICD-10 Code K26.0. Three documentation elements are critical before a coder can assign this code with confidence.

• Explicit documentation of hemorrhage. The clinician must document active bleeding, hematemesis, melena, or endoscopic confirmation of a bleeding duodenal ulcer. Inferred bleeding is not sufficient for K26.0.
• Acute designation supported by clinical record. Duration of symptoms, endoscopic appearance, and clinical course should distinguish acute from chronic. Without this, default to K26.4.
• HIPAA transaction compliance. ICD-10 Code K26.0 is valid for all HIPAA-covered electronic transactions in FY2026. Payer-specific policies may require supporting documentation attached to the claim.

Practices that use digital intake forms and structured clinical templates reduce the missing details that cause coder uncertainty. Standardizing how hemorrhage severity and ulcer duration are captured at the point of care directly reduces coding ambiguity downstream. For practices building compliant digital record workflows, patient data security in clinical workflows also affects how coded encounter data is stored and transmitted.

Two etiologies account for the overwhelming majority of acute duodenal ulcers with hemorrhage: H. pylori infection and NSAID use. The ICD-10-CM guidelines allow, and in some payer contexts require, additional codes to capture these causal relationships alongside ICD-10 Code K26.0.

Assigning B96.81 requires a confirmed positive test (CLO test, histology, breath test, or serology per clinical context) documented by the treating physician. Z79.1 requires documented long-term NSAID use, not incidental or one-off use. Confirm the etiology before coding either secondary code.

For GP clinic software workflows that handle GI referrals, embedding etiology capture fields into encounter templates makes this step systematic rather than ad hoc.

K26.0 and upper GI bleed: coding the complication

A frequent coding decision point: when a patient presents with acute upper GI bleeding and investigation confirms a duodenal ulcer, should the coder assign ICD-10 Code K26.0 alone, or also assign a separate hemorrhage code such as K92.1 (melena) or K92.2 (gastrointestinal hemorrhage, unspecified)?

The ICD-10-CM Official Guidelines provide clear direction. K26.0 already incorporates the hemorrhage – it is part of the code description, not a separate complication. Assigning K92.1 or K92.2 in addition to K26.0 when the bleed has a confirmed source (the duodenal ulcer) is generally redundant and may trigger an edit. The exception is when:

• The hemorrhage is a clinically distinct, separately managed finding beyond the ulcer itself (for example, a concurrent GI bleed from a different anatomical site).
• The documentation specifically addresses the hemorrhage as a separate diagnosis requiring independent clinical management.
• Payer or DRG grouper rules for the specific facility require explicit hemorrhage coding for appropriate reimbursement tier assignment.

When uncertain, query the treating clinician. The principle is that ICD-10 Code K26.0 captures the complete clinical picture for most acute hemorrhagic duodenal ulcer encounters. For a related hemorrhage symptom code, K92.0 follows the same complication-included logic when hematemesis is the only documented finding. Accurate sequencing of the principal diagnosis also matters when secondary diagnoses must be sequenced correctly.

Streamline GI billing documentation with Pabau

Pabau's structured clinical records and documentation tools help gastroenterology and general practice teams capture ICD-10 Code K26.0 encounters accurately, including etiology fields at the point of care, for cleaner, audit-ready charting.

Book a demo

Related ICD-10 codes for duodenal ulcer and GI hemorrhage

Coders working with ICD-10 Code K26.0 frequently cross-reference adjacent GI ulcer and hemorrhage codes. The table below covers the most commonly used related codes, verified against the ICD List ICD-10-CM database.

For practices managing GI billing across multiple providers, structured practice management software can link diagnosis codes to encounter-level templates, reducing the manual lookup time per claim. The HIPAA compliance guidance applicable to claim data handling also applies to how these coded records are stored and shared between referring and treating clinicians.

Conclusion

ICD-10 Code K26.0 is a straightforward but specificity-dependent code: the acute designation and the hemorrhage qualifier both require explicit clinician documentation before a coder can assign it with confidence. Getting the K26 subcode wrong – defaulting to K26.9 when K26.0 is warranted, or missing the B96.81 or Z79.1 additional codes – leads to undercoded encounters and potential audit risk.

Pabau’s structured clinical documentation and EMR workflows give gastroenterology and general practice teams the tools to capture hemorrhage specificity, etiology, and acuity at the point of care. Book a demo to see how Pabau handles ICD-10-CM documentation in practice.

Continue your research

Need a documentation template for a related GI condition? Appendicitis nursing care plan shows how structured care planning keeps abdominal-complaint documentation audit-ready.

Want to capture gut-health etiology systematically? Functional medicine matrix illustrates a root-cause documentation framework that pairs well with H. pylori and NSAID etiology capture.

Looking for another example of documentation-driven code specificity? ICD-10 Code M35.3 shows how the same specificity requirements play out in a different code family.

Frequently asked questions