2026 ICD-10-CM Diagnosis Code L21.0Seborrhea capitis

ICD-10-CM Codes›L00–L99›L20-L30›L21

ICD-10-CM L21.0
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

L21.0 is a billable ICD-10-CM diagnosis code for seborrhea capitis. 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. Coders also document this condition as cradle cap. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified inflammatory condition of skin.

Code Identity

ICD-10-CM Code
L21.0
Billable Status
Yes — Valid for Submission
Code Describes
Seborrhea capitis
Short Description
Seborrhea capitis
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 CodeL21.0Seborrhea capitis

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Cradle cap
  • Exfoliative disorder of skin of scalp
  • Pityriasis
  • Pityriasis capitis
  • Pityriasis steatoides
  • Seborrheic dermatitis of scalp

Tabular List NotesGuidance

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

Inclusion Terms

  • Cradle cap

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.

    • Cradle cap
    • Crusta lactea
    • Dandruff
    • Furfur
    • Milk
      • crust
    • Pityriasis(capitis)
    • Pityriasis(capitis)
      • furfuracea
    • Seborrhea, seborrheic
      • capitis
    • Seborrhea, seborrheic
      • sicca

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

  • Pityriasis

    a name originally applied to a group of skin diseases characterized by the formation of fine, branny scales, but now used only with a modifier. (dorland, 27th ed)

  • Pityriasis Lichenoides

    a subgroup of parapsoriasis itself divided into acute and chronic forms. the acute form is characterized by the abrupt onset of a generalized, reddish-brown, maculopapular eruption. lesions may be vesicular, hemorrhagic, crusted, or necrotic. histologically the disease is characterized by epidermal necrolysis. the chronic form shows milder skin changes with necrosis.

  • Pityriasis Rosea

    a mild exanthematous inflammation of unknown etiology. it is characterized by the presence of salmon-colored maculopapular lesions. the most striking feature is the arrangement of the lesions such that the long axis is parallel to the lines of cleavage. the eruptions are usually generalized, affecting chiefly the trunk, and the course is often self-limiting.

  • Pityriasis Rubra Pilaris

    a chronic skin disease characterized by small follicular papules, disseminated reddish-brown scaly patches, and often, palmoplantar hyperkeratosis. the papules are about the size of a pin and topped by a horny plug.

  • Tinea Versicolor

    a common chronic, noninflammatory and usually symptomless disorder, characterized by the occurrence of multiple macular patches of all sizes and shapes, and varying in pigmentation from fawn-colored to brown. it is seen most frequently in hot, humid, tropical regions and is mostly caused by malassezia furfur (formerly pityrosporum orbiculare).

  • Parapsoriasis

    the term applied to a group of relatively uncommon inflammatory, maculopapular, scaly eruptions of unknown etiology and resistant to conventional treatment. eruptions are both psoriatic and lichenoid in appearance, but the diseases are distinct from psoriasis, lichen planus, or other recognized dermatoses. proposed nomenclature divides parapsoriasis into two distinct subgroups, pityriasis lichenoides and parapsoriasis en plaques (small- and large-plaque parapsoriasis).

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 L21.0 to ICD-9-CMHistory

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

ICD-9-CM
690.11 Seborrhea capitis
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 L21.0Overview

Is L21.0 (Seborrheic dermatitis) a billable code?

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

What MS-DRG does L21.0 group to?

When seborrhea capitis 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.

What is the ICD-9 equivalent of L21.0?

Under the General Equivalence Mappings, seborrhea capitis converts to ICD-9-CM 690.11 (seborrhea capitis). 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.