K12.3 Oral mucositis (ulcerative)

⚠ Non-Billable ICD-10-CM 2026
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The ICD-10-CM code for Oral mucositis (ulcerative) is K12.3 (FY2026). It is a non-billable category code — select a more specific code below for claims.

Classification

Section
K00-K14: Diseases of oral cavity and salivary glands (K00-K14)
Category K12
10 codes (8 billable)
FY2026 Status
Stable since FY2024
Excludes2
Not included here. These conditions are coded elsewhere but may be coded together if applicable.
  • gastrointestinal mucositis (ulcerative) (K92.81)
  • mucositis (ulcerative) of vagina and vulva (N76.81)
  • nasal mucositis (ulcerative) (J34.81)

Inclusion Terms

  • Mucositis (oral) (oropharyneal)

Official Coding Guidelines

Chapter 11 reserved for future expansion

11. Chapter 11: Diseases of the Digestive System (K00-K95) Reserved for future guideline expansion

— ICD-10-CM Official Guidelines for Coding and Reporting, FY2026, Section I.C.11

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

Cite This Page

Reference K12.3 with the canonical source and edition:

K12.3 — Oral mucositis (ulcerative). ICD-10 Coding Pro (ICD-10-CM FY2026). https://icd10codingpro.com/codes/K12.3

Canonical URL: https://icd10codingpro.com/codes/K12.3

Related Codes

Parent Code

K12 Stomatitis and related lesions

More Specific Codes

K12.30 Oral mucositis (ulcerative), unspecified K12.31 Oral mucositis (ulcerative) due to antineoplastic therapy K12.32 Oral mucositis (ulcerative) due to other drugs K12.33 Oral mucositis (ulcerative) due to radiation K12.39 Other oral mucositis (ulcerative)

Related Codes in K12

K12 Stomatitis and related lesions K12.0 Recurrent oral aphthae K12.1 Other forms of stomatitis K12.2 Cellulitis and abscess of mouth K12.30 Oral mucositis (ulcerative), unspecified K12.31 Oral mucositis (ulcerative) due to antineoplastic therapy K12.32 Oral mucositis (ulcerative) due to other drugs K12.33 Oral mucositis (ulcerative) due to radiation K12.39 Other oral mucositis (ulcerative)
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Reviewed by Prajwal Shrestha, CPC, CRC
Certified Professional Coder (CPC) and Certified Risk Adjustment Coder (CRC) · AAPC Member ID 01997614 · About · Editorial policy · Content last reviewed: 2025-10-01

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