2026 ICD-10-CM Diagnosis Code K12.32Oral mucositis (ulcerative) due to other drugs

ICD-10-CM Codes›K00–K95›K00-K14›K12

ICD-10-CM K12.32
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

K12.32 is a billable ICD-10-CM diagnosis code for oral mucositis (ulcerative) due to other drugs. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 157 through 159. Coders also document this condition as adverse reaction to platelet aggregation inhibitor. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Any dental condition including traumatic injury, Diseases of mouth; excluding dental, and Drug induced or toxic related condition.

Code Identity

ICD-10-CM Code
K12.32
Billable Status
Yes — Valid for Submission
Code Describes
Oral mucositis (ulcerative) due to other drugs
Short Description
Oral mucositis (ulcerative) due to other drugs
Same as the full description in the CMS dataset.
Parent Code
K12.3
Oral mucositis (ulcerative)

Code Classification

ChapterK00–K95Diseases of the digestive system
SectionK00-K14Diseases of oral cavity and salivary glands
CategoryK12Stomatitis and related lesions
This CodeK12.32Oral mucositis (ulcerative) due to other drugs

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Adverse reaction to platelet aggregation inhibitor
  • Adverse reaction to salicylate
  • Aspirin adverse reaction
  • Aspirin burn of oral mucosa
  • Drug-induced mucositis
  • Stomatitis medicamentosa

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Use Additional Code

  • code for adverse effect, if applicable, to identify drug T36 T50

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Mucositis(ulcerative)
      • due to drugs NEC
    • Mucositis(ulcerative)
      • mouth (oral) (oropharyngeal)
        • due to drugs NEC

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR DEN001
Any dental condition including traumatic injury
Default principal diagnosis: inpatient No · outpatient No
CCSR DIG003
Diseases of mouth; excluding dental
Default principal diagnosis: inpatient No · outpatient No
CCSR INJ030
Drug induced or toxic related condition
Default principal diagnosis: inpatient Yes · outpatient Yes
CCSR DEN002
Nontraumatic dental conditions
Default principal diagnosis: inpatient No · outpatient No

Patient EducationClinical

Drug Reactions

Most of the time, medicines make our lives better. They reduce aches and pains, fight infections, and control problems such as high blood pressure or diabetes. But medicines can also cause unwanted reactions, such as drug interactions, side effects, and allergies.

The full article covers:

  • What is a drug interaction?
  • What are side effects?
  • What are drug allergies?
  • How can I stay safe when taking medicines?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert K12.32 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
528.02 Mucositis d/t drugs NEC
Exact Match The mapping is direct, with no qualifiers.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About K12.32Overview

Is K12.32 (Oral mucositis (ulcerative)) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report oral mucositis (ulcerative) due to other drugs on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does K12.32 group to?

When oral mucositis (ulcerative) due to other drugs is the principal diagnosis on an inpatient stay, it groups to MS-DRG 157, 158, 159, with relative weights from 0.7085 to 1.7168 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of K12.32?

Under the General Equivalence Mappings, oral mucositis (ulcerative) due to other drugs converts to ICD-9-CM 528.02 (mucositis d/t drugs NEC). The mapping is a direct match.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.