Coding and coverage · ICD-10-CM

K12

K12.3 Oral mucositis (ulcerative)

Not billable (header)Chapter 11

Report one of the more specific codes below.

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Codes under this one

  • 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)

Instructional notes

Chapter 11

Excludes2Not included here: the patient may have both; report both when both are present.
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

K12

Excludes1Not coded here: never report with this code, except when the two conditions are unrelated.
  • cancrum oris (A69.0)
  • cheilitis (K13.0)
  • gangrenous stomatitis (A69.0)
  • herpesviral [herpes simplex] gingivostomatitis (B00.2)
  • noma (A69.0)
Use additional codeAdd a second code for the full picture.
  • code to identify:
  • alcohol abuse and dependence (F10.-)
  • exposure to environmental tobacco smoke (Z77.22)
  • exposure to tobacco smoke in the perinatal period (P96.81)
  • history of tobacco dependence (Z87.891)
  • occupational exposure to environmental tobacco smoke (Z57.31)
  • tobacco dependence (F17.-)
  • tobacco use (Z72.0)

This code

Excludes2Not included here: the patient may have both; report both when both are present.
  • gastrointestinal mucositis (ulcerative) (K92.81)
  • mucositis (ulcerative) of vagina and vulva (N76.81)
  • nasal mucositis (ulcerative) (J34.81)
Inclusion terms
  • Mucositis (oral) (oropharyneal)

Chapter 11: Diseases of the digestive system · K00-K14 Diseases of oral cavity and salivary glands (K00-K14)

Source: ICD-10-CM FY 2027 code descriptions and tabular list (CMS and CDC National Center for Health Statistics), effective 2026-10-01 through 2027-09-30 · CMS ICD-10 files. HCC mapping: CMS-HCC V28, payment year 2027. As of 2026-11-04.

Coverage and payment depend on the claim details; confirm with the Medicare Administrative Contractor.