2026 ICD-10-CM Diagnosis Code L21.1Seborrheic infantile dermatitis

ICD-10-CM Codes›L00–L99›L20-L30›L21

ICD-10-CM L21.1
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

L21.1 is a billable ICD-10-CM diagnosis code for seborrheic infantile dermatitis. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 606 through 607. The code is restricted by the Medicare Code Editor to pediatric patients (age 0 through 17). In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified inflammatory condition of skin.

Code Identity

ICD-10-CM Code
L21.1
Billable Status
Yes — Valid for Submission
Code Describes
Seborrheic infantile dermatitis
Short Description
Seborrheic infantile dermatitis
Same as the full description in the CMS dataset.
Parent Code
L21
Seborrheic dermatitis

Code Classification

ChapterL00–L99Diseases of the skin and subcutaneous tissue
SectionL20-L30Dermatitis and eczema
CategoryL21Seborrheic dermatitis
This CodeL21.1Seborrheic infantile dermatitis

Code EditsBilling

Medicare Code Editor checks that affect claim validity for L21.1.

Pediatric diagnoses
The Medicare Code Editor detects inconsistencies in pediatric cases by checking a patient's age and any diagnosis on the patient's record. The pediatric code edits apply to patients age range is 0–17 years inclusive (e.g., Reye's syndrome, routine child health exam).

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute seborrheic dermatitis
  • Chronic seborrheic dermatitis
  • Generalized seborrheic dermatitis of infants
  • Greasy skin
  • Sebaceous hyperplasia
  • Seborrhea adiposa
  • Seborrhea corporis
  • Seborrhea faciei
  • Seborrhea nasi
  • Seborrheic blepharitis
  • Seborrheic dermatitis
  • Seborrheic eczema-like eruption
  • Truncal seborrheic dermatitis

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.

    • Dermatitis(eczematous)
      • seborrheic
        • infantile
    • Eczema(acute) (chronic) (erythematous) (fissum) (rubrum) (squamous)
      • infantile (due to any substance)
        • intertriginous
    • Eczema(acute) (chronic) (erythematous) (fissum) (rubrum) (squamous)
      • infantile (due to any substance)
        • seborrheic
    • Eczema(acute) (chronic) (erythematous) (fissum) (rubrum) (squamous)
      • intertriginous NEC
        • infantile
    • Erythroderma(secondary)
      • desquamativum
    • Leiner's disease
    • Seborrhea, seborrheic
      • dermatitis
        • infantile
    • Seborrhea, seborrheic
      • eczema
        • infantile

Clinical ClassificationClinical

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

CCSR SKN002
Other specified inflammatory condition of skin
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Sebaceous Hyperplasia

    enlargement of the sebaceous glands.

  • Senile Sebaceous Hyperplasia

    a hyperplasia of the sebaceous glands. it is usually seen as small yellow papules in the face of middle aged-older population.

Patient EducationClinical

Dandruff, Cradle Cap, and Other Scalp Conditions

Your scalp is the skin on the top of your head. Unless you have hair loss, hair grows on your scalp. Different skin problems can affect your scalp.

Read the full article at MedlinePlus

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

Convert L21.1 to ICD-9-CMHistory

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

ICD-9-CM
690.12 Sbrheic infantl drmtitis
Approximate The match is approximate rather than exact.

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 L21.1Overview

Is L21.1 (Seborrheic dermatitis) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report seborrheic infantile dermatitis on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does L21.1 group to?

When seborrheic infantile dermatitis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 606, 607, with relative weights from 0.9064 to 1.5132 depending on complications. Higher weights mean higher Medicare reimbursement.

Who can L21.1 be reported for?

The Medicare Code Editor checks seborrheic infantile dermatitis against patient demographics: this code is intended for pediatric patients (age 0 through 17). Claims outside these limits are flagged as inconsistent.

What is the ICD-9 equivalent of L21.1?

Under the General Equivalence Mappings, seborrheic infantile dermatitis converts to ICD-9-CM 690.12 (sbrheic infantl drmtitis). The mapping is approximate, so confirm the match fits the documentation.

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.