K29.8 ICD-10-CM Code: Duodenitis
Billing Status: NO. This is a clinician non-billable / parent hierarchy grouping in the ICD-10-CM system.
Coding at a Glance
- Tabular directives
- 2 Excludes1 · 1 Excludes2
Coding instructions
Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for K29.8 in the official ICD-10-CM tabular list, quoted as published.
Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2026Effective: October 1, 2025
Notes without a marker are published on K29.8 itself; “inherited from” names the category or block whose note applies here.
Excludes1 — Not Coded Here
Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
- eosinophilic gastritis or gastroenteritis (K52.81) Compare K29.8 vs K52.81 →
- Zollinger-Ellison syndrome (E16.4) Compare K29.8 vs E16.4 →
Source: inherited from K29
Excludes2 — Not Included Here
Conditions not covered by this code, but which may be reported alongside it when both are present.
- hiatus hernia (K44.-) Compare K29.8 vs K44 →
Source: inherited from K20-K31
Coder workflow for K29.8
MedCoder structured workflow — derived from this code’s own official record
Before you code K29.8
- K29.8 is not reportable as written. Select the more specific code beneath it that the documentation supports. Codes are reported to the highest level of specificity the classification provides (Guidelines I.B.2).
See the relationships section · Guide: How to choose an ICD-10-CM code →
- Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with K29.8. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).
Choose the right path
- Does the documentation support one of the more specific codes beneath K29.8?
Yes → Select that code and continue the checks below on its own page.
No → K29.8 cannot be reported as written; query for the specificity its subcategory needs. - Does the documentation support a condition named in K29.8’s Excludes1 note?
Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
No → Continue.
Consider K29.8. Then confirm the code is valid for the date of service in the Verify section.
Documentation check
- The provider’s diagnostic statement
- Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).
- Acuity
- Acute or chronic as documented; when both are documented and separate codes exist, both are reported with the acute code first (Guidelines I.B.8).
Official instructions as workflow
Excludes1 — check before selecting K29.8(2 notes)
Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with K29.8: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.
See the official tabular notes · Guidelines I.A.12.a
Excludes2 — not part of K29.8(1 note)
Coding workflow: The conditions named in this note are not included in K29.8. When the record documents both, both may be reported; the note is a boundary, not a prohibition.
CompareK44
See the official tabular notes · Guidelines I.A.12.b
Coding decision scenarios
Pattern scenarios for this code’s structure — decision rules, not clinical cases
Documentation: Both the condition K29.8 describes and a condition named in its Excludes1 note are documented for the same encounter.
Coding question: Can both codes be reported?
Path: Review the Excludes1 note and the excluded code, and look for a provider statement on whether the two conditions are related.
Reason: Excludes1 means the two are not coded together; the exception is when the record shows the conditions are unrelated to each other (Guidelines I.A.12.a).
Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.
Code Overview
MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.
Verify Before Coding
From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.
Relationships & Classification
MedCoder structured relationships — computed from published CMS and AHRQ datasets
Other codes that name K29.8 or its code family, from the CMS ICD-10-CM tabular instructional notes. Tabular-note edges are stored at the code family level that carries each note.
Referenced by 1 Excludes1 note: K92.2 — Gastrointestinal hemorrhage, unspecified (via K29.-).
These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.
Referenced by 21 Code First instructions: T36 — Poisoning by, adverse effect of and underdosing of systemic antibiotics (via K29.-), T36-T39 — Antibiotics & Anti-infectives (T36-T39) (via K29.-), T36-T50 — Poisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances (T36-T50) (via K29.-), T37 — Poisoning by, adverse effect of and underdosing of other systemic anti-infectives and antiparasitics (via K29.-), T38 — Poisoning by, adverse effect of and underdosing of hormones and their synthetic substitutes and antagonists, not elsewhere classified (via K29.-), T39 — Poisoning by, adverse effect of and underdosing of nonopioid analgesics, antipyretics and antirheumatics (via K29.-), T40 — Poisoning by, adverse effect of and underdosing of narcotics and psychodysleptics [hallucinogens] (via K29.-), T40-T41 — Analgesics & Antipyretics (T40-T41) (via K29.-), T41 — Poisoning by, adverse effect of and underdosing of anesthetics and therapeutic gases (via K29.-), T42 — Poisoning by, adverse effect of and underdosing of antiepileptic, sedative- hypnotic and antiparkinsonism drugs (via K29.-), T42-T43 — Anticonvulsants & Psychotropics (T42-T43) (via K29.-), T43 — Poisoning by, adverse effect of and underdosing of psychotropic drugs, not elsewhere classified (via K29.-), T44 — Poisoning by, adverse effect of and underdosing of drugs primarily affecting the autonomic nervous system (via K29.-), T44-T46 — Cardiovascular & Gastrointestinal (T44-T46) (via K29.-), T45 — Poisoning by, adverse effect of and underdosing of primarily systemic and hematological agents, not elsewhere classified (via K29.-), T46 — Poisoning by, adverse effect of and underdosing of agents primarily affecting the cardiovascular system (via K29.-), T47 — Poisoning by, adverse effect of and underdosing of agents primarily affecting the gastrointestinal system (via K29.-), T47-T50 — Hormones & Systemic Agents (T47-T50) (via K29.-), T48 — Poisoning by, adverse effect of and underdosing of agents primarily acting on smooth and skeletal muscles and the respiratory system (via K29.-), T49 — Poisoning by, adverse effect of and underdosing of topical agents primarily affecting skin and mucous membrane and by ophthalmological, otorhinorlaryngological and dental drugs (via K29.-), +1 more.
Each of these codes carries a Code First note naming this condition — when that code is reported, THIS code is sequenced first, ahead of it.
Contextual Map
Every relationship of K29.8 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.
Run K29.8 with these 9 related codes in Claim Check
Hierarchy
- K00-K95 — Chapter 11: Diseases of the Digestive System (K00-K95) (K00-K95)[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K20-K31 — Diseases of esophagus, stomach and duodenum[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
Referenced by Excludes1 notes
- K92.2 — Gastrointestinal hemorrhage, unspecified[Excludes1](via K29.-): “gastritis and duodenitis with hemorrhage (K29.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
Referenced by Code First instructions (21)
- T36 — Poisoning by, adverse effect of and underdosing of systemic antibiotics[Code First](via K29.-): “aspirin gastritis (K29.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- T36-T39 — Antibiotics & Anti-infectives (T36-T39)[Code First](via K29.-): “aspirin gastritis (K29.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- T36-T50 — Poisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances (T36-T50)[Code First](via K29.-): “aspirin gastritis (K29.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- T37 — Poisoning by, adverse effect of and underdosing of other systemic anti-infectives and antiparasitics[Code First](via K29.-): “aspirin gastritis (K29.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- T38 — Poisoning by, adverse effect of and underdosing of hormones and their synthetic substitutes and antagonists, not elsewhere classified[Code First](via K29.-): “aspirin gastritis (K29.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- T39 — Poisoning by, adverse effect of and underdosing of nonopioid analgesics, antipyretics and antirheumatics[Code First](via K29.-): “aspirin gastritis (K29.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- T40 — Poisoning by, adverse effect of and underdosing of narcotics and psychodysleptics [hallucinogens][Code First](via K29.-): “aspirin gastritis (K29.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- T40-T41 — Analgesics & Antipyretics (T40-T41)[Code First](via K29.-): “aspirin gastritis (K29.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- and 13 more
Nearest codes (27)
- K29 — Gastritis and duodenitis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K29.0 — Acute gastritis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K29.00 — Acute gastritis without bleeding[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K29.01 — Acute gastritis with bleeding[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K29.2 — Alcoholic gastritis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K29.20 — Alcoholic gastritis without bleeding[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K29.21 — Alcoholic gastritis with bleeding[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- K29.3 — Chronic superficial gastritis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- and 19 more
Change history
- FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016
Common coding questions
Can K29.8 be billed directly?
No. K29.8 (Duodenitis) is a non-billable ICD-10-CM category code. A more specific billable subcode must be selected based on clinical documentation.
Sources for this page
Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.
- Code, title, tabular notes and index terms Official source data
- CMS/CDC ICD-10-CM FY2026 tabular list, index and tables, effective October 1, 2025 Release, file and checksum · Publisher’s page
- Claim edits Official source data
- CMS Definitions of Medicare Code Edits — v43.1 (April 2026) Release, file and checksum · Publisher’s page
- Change history and date-of-service validity Official source data
- CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
- Comparisons, relationships and the contextual map MedCoder structured relationship
- Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
- Summary and FAQ answers MedCoder explanation
- Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.
Labels on this page: Official source data · MedCoder structured relationship · MedCoder explanation. How to read the labels · All data sources and release dates
Cite this page
Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.
MedCoder.ai. "K29.8 — Duodenitis." ICD-10-CM FY2026. https://medcoder.ai/icd10/code/k29.8-duodenitis
Change history
- FY2016 — October 1, 2015In the code set at ICD-10-CM adoptionDuodenitis
No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027 (effective October 1, 2026), and none are recorded for this code. Note changes are tracked from FY2027 only.
Nearest Codes in This Family
Official ICD-10-CM classifications closest to K29.8 in its code family, with their registry titles.
- K29.60 — Other gastritis without bleeding
- K29.61 — Other gastritis with bleeding
- K29.7 — Gastritis, unspecified
- K29.70 — Gastritis, unspecified, without bleeding
- K29.71 — Gastritis, unspecified, with bleeding
- K29.80 — Duodenitis without bleeding
- K29.81 — Duodenitis with bleeding
- K29.9 — Gastroduodenitis, unspecified
- K29.90 — Gastroduodenitis, unspecified, without bleeding
- K29.91 — Gastroduodenitis, unspecified, with bleeding